Update to 1.23

Upstream changes:
Version 1.23, 2014-08-11
------------------------

 - Documentation now available at http://pythonhosted.org//PyPDF2

 - Bugfix in pagerange.py for when __init__.__doc__ has no value (by
   Vladir Cruz)

 - Fix typos in OutlinesObject().add() (by shilluc)

 - Re-added a missing return statement in a utils.py method

 - Corrected viewing mode names (by Jason Scheirer)

 - New PdfFileWriter method: addJS() (by vfigueiro)

 - New bookmark features: color, boldness, italics, and page fit
   (by Joshua Arnott)

 - New PdfFileReader method: getFields(). Used to extract field
   information from PDFs with interactive forms. See documentation
   for details

 - Converted README file to markdown format (by Stephen Bussard)

 - Several improvements to overall performance and efficiency
   (by mozbugbox)

 - Fixed a bug where geospatial information was not scaling along with
   its page

 - Fixed a type issue and a Python 3 issue in the decryption algorithms
   (with Francisco Vieira and koba-ninkigumi)

 - Fixed a bug causing an infinite loop in the ASCII 85 decoding
   algorithm (by madmaardigan)

 - Annotations (links, comment windows, etc.) are now preserved when
   pages are merged together

 - Used the Destination class in addLink() and addBookmark() so that
   the page fit option could be properly customized

Version 1.22, 2014-05-29
------------------------

 - Added .DS_Store to .gitignore (for Mac users) (by Steve Witham)

 - Removed __init__() implementation in NameObject (by Steve Witham)

 - Fixed bug (inf. loop) when merging pages in Python 3 (by commx)

 - Corrected error when calculating height in scaleTo()

 - Removed unnecessary code from DictionaryObject (by Georges Dubus)

 - Fixed bug where an exception was thrown upon reading a NULL string
   (by speedplane)

 - Allow string literals (non-unicode strings in Python 2) to be passed
   to PdfFileReader

 - Allow ConvertFunctionsToVirtualList to be indexed with slices and
   longs (in Python 2) (by Matt Gilson)

 - Major improvements and bugfixes to addLink() method (see documentation
   in source code) (by Henry Keiter)

 - General code clean-up and improvements (with Steve Witham and Henry Keiter)

 - Fixed bug that caused crash when comments are present at end of
   dictionary

Version 1.21, 2014-04-21
------------------------

 - Fix for when /Type isn't present in the Pages dictionary (by Rob1080)

 - More tolerance for extra whitespace in Indirect Objects

 - Improved Exception handling

 - Fixed error in getHeight() method (by Simon Kaempflein)

 - implement use of utils.string_type to resolve Py2-3 compatibility issues

 - Prevent exception for multiple definitions in a dictionary (with carlosfunk)
   (only when strict = False)

 - Fixed errors when parsing a slice using pdfcat on command line (by
   Steve Witham)

 - Tolerance for EOF markers within 1024 bytes of the actual end of the
   file (with David Wolever)

 - Added overwriteWarnings parameter to PdfFileReader constructor, if False
   PyPDF2 will NOT overwrite methods from Python's warnings.py module with
   a custom implementation.

 - Fix NumberObject and NameObject constructors for compatibility with PyPy
   (R▒diger Jungbeck, Xavier Dupr▒, shezadkhan137, Steven Witham)

 - Utilize  utils.Str in pdf.py and pagerange.py to resolve type issues (by
   egbutter)

 - Improvements in implementing StringIO for Python 2 and BytesIO for
   Python 3 (by Xavier Dupr▒)

 - Added /x00 to Whitespaces, defined utils.WHITESPACES to clarify code (by
   Maxim Kamenkov)

 - Bugfix for merging 3 or more resources with the same name (by lucky-user)

 - Improvements to Xref parsing algorithm (by speedplane)

Version 1.20, 2014-01-27
------------------------

 - Official Python 3+ support (with contributions from TWAC and cgammans)
   Support for Python versions 2.6 and 2.7 will be maintained

 - Command line concatenation (see pdfcat in sample code) (by Steve Witham)

 - New FAQ; link included in README

 - Allow more (although unnecessary) escape sequences

 - Prevent exception when reading a null object in decoding parameters

 - Corrected error in reading destination types (added a slash since they
   are name objects)

 - Corrected TypeError in scaleTo() method

 - addBookmark() method in PdfFileMerger now returns bookmark (so nested
   bookmarks can be created)

 - Additions to Sample Code and Sample PDFs

 - changes to allow 2up script to work (see sample code) (by Dylan McNamee)

 - changes to metadata encoding (by Chris Hiestand)

 - New methods for links: addLink() (by Enrico Lambertini) and removeLinks()

 - Bugfix to handle nested bookmarks correctly (by Jamie Lentin)

 - New methods removeImages() and removeText() available for PdfFileWriter
   (by Tien Ha▒)

 - Exception handling for illegal characters in Name Objects

Version 1.19, 2013-10-08
------------------------

BUGFIXES:
 - Removed pop in sweepIndirectReferences to prevent infinite loop
   (provided by ian-su-sirca)

 - Fixed bug caused by whitespace when parsing PDFs generated by AutoCad

 - Fixed a bug caused by reading a 'null' ASCII value in a dictionary
   object (primarily in PDFs generated by AutoCad).

FEATURES:
 - Added new folders for PyPDF2 sample code and example PDFs; see README
   for each folder

 - Added a method for debugging purposes to show current location while
   parsing

 - Ability to create custom metadata (by jamma313)

 - Ability to access and customize document layout and view mode
   (by Joshua Arnott)

OTHER:
 - Added and corrected some documentation

 - Added some more warnings and exception messages

 - Removed old test/debugging code

UPCOMING:
 - More bugfixes (We have received many problematic PDFs via email, we
   will work with them)

 - Documentation - It's time for PyPDF2 to get its own documentation
   since it has grown much since the original pyPdf

 - A FAQ to answer common questions


(wen)