Update to 2.11

Upstream changes:
2.11 2015-12-08 CADE
  - fixed smoothing delta range and default parameter.

2.10 2015-12-08 NEILB CADE
  - Added 'smoothing' option which makes the estimated time remaining
    monotically decreasing most of the time, preventing flicker.
  - Added option to change default smoothing delta parameter.

2.00 2015-09-01 CADE
  - version bump (CPAN release cleanup)

1.91 2015-08-23 CADE (changes from NEILB)
  - Removed redundant =cut at the end of the file, which was resulting
    in a pod warning.
  - Added a SEE ALSO section to the pod.
  - Shortened the SYNOPSIS and expanded the DESCRIPTION.

1.9 2015-08-23 CADE (changes from NEILB)
  - Added some basic tests that are checking correct behaviour.
  - Removed META.yml from repo, as it's generated by ExtUtils::MakeMaker
  - Changed two uses of indirect method notation in the doc to use direct.
  - Moved demo.pl to examples/demo.pl
  - Dropped usage of Exporter, as the module doesn't export anything.
  - Specified min perl version as 5.006 in code and dist metadata.
  - Added prereqs to Makefile.PL
  - Github repo now listed in the dist metadata.
  - Added COPYRIGHT AND LICENSE section to doc
  - Reformatted this file as per CPAN::Changes::Spec

(wen)