Update py-PDF2 to 1.25.1

Patch 1.25.1, 2015-07-20

- Fix bug when parsing inline images. Occurred when merging
  certain pages with inline images

- Fixed type error when creating outlines by utilizing the
  isString() test

Version 1.25, 2015-07-07
------------------------

BUGFIXES:

- Added Python 3 algorithm for ASCII85Decode. Fixes issue when
  reading reportlab-generated files with Py 3 (jerickbixly)

- Recognize more escape sequence which would otherwise throw an
  exception (manuelzs, robertsoakes)

- Fixed overflow error in generic.py. Occurred
  when reading a too-large int in Python 2 (by Raja Jamwal)

- Allow access to files which were encrypted with an empty
  password. Previously threw a "File has not been decrypted"
  exception (Elena Williams)

- Do not attempt to decode an empty data stream. Previously
  would cause an error in decode algorithms (vladir)

- Fixed some type issues specific to Py 2 or Py 3

- Fix issue when stream data begins with whitespace (soloma83)

- Recognize abbreviated filter names (AlmightyOatmeal and
  Matthew Weiss)

- Copy decryption key from PdfFileReader to PdfFileMerger.
  Allows usage of PdfFileMerger with encrypted files (twolfson)

- Fixed bug which occurred when a NameObject is present at end
  of a file stream. Threw a "Stream has ended unexpectedly"
  exception (speedplane)

FEATURES:

- Initial work on a test suite; to be expanded in future.
  Tests and Resources directory added, README updated (robertsoakes)

- Added document cloning methods to PdfFileWriter:
  appendPagesFromReader, cloneReaderDocumentRoot, and
  cloneDocumentFromReader. See official documentation (robertsoakes)

- Added method for writing to form fields: updatePageFormFieldValues.
  This will be enhanced in the future. See official documentation
  (robertsoakes)

- New addAttachment method. See documentation. Support for adding
  and extracting embedded files to be enhanced in the future
  (moshekaplan)

- Added methods to get page number of given PageObject or
  Destination: getPageNumber and getDestinationPageNumber.
  See documentation (mozbugbox)

OTHER ENHANCEMENTS:

- Enhanced type handling (Brent Amrhein)

- Enhanced exception handling in NameObject (sbywater)

- Enhanced extractText method output (peircej)

- Better exception handling

- Enhanced regex usage in NameObject class (speedplane)

Version 1.24, 2014-12-31
------------------------

- Bugfixes for reading files in Python 3 (by Anthony Tuininga and
  pqqp)

- Appropriate errors are now raised instead of infinite loops (by
  naure and Cyrus Vafadari)

- Bugfix for parsing number tokens with leading spaces (by Maxim
  Kamenkov)

- Don't crash on bad /Outlines reference (by eshellman)

- Conform tabs/spaces and blank lines to PEP 8 standards

- Utilize the readUntilRegex method when reading Number Objects
  (by Brendan Jurd)

- More bugfixes for Python 3 and clearer exception handling

- Fixed encoding issue in merger (with eshellman)

- Created separate folder for scripts

(kleink)