On release merge to master/debian branches.

On hotfix we should merge to master/debian branches. On release, merge with the
develop/debian-develop branches and the master/debian branches.
Edit changelog after ending a feature
Ask user before edit changelog
Propose a changelog based on the feature commits
Merge branch 'feature-changelog' into develop
Heavily modify flow code.

Add argument parser for input.
Add interactive functions for cleanup and changelog editing
Add automatic version bumping.
Merge branch 'feature-autoversion' into develop
Split version validation from version generating
Make bump version modular.

Add a _bump version function without any validation checking. Use the new
validate_version to perform the validation.
Strip rc from version when ending a release
Fix debian tag when finishing release
Update changelog
Merge branch 'feature-fix-release-version' into develop
Prefix commit message in changelog with '* '
Update changelog
Merge branch 'feature-improve-changelog' into develop
Replace README with updated README.md.
Make "Quickstart" a 2nd-level header in README.md
Fix typo in setup and MANIFEST files

s/README/README.md
Allow multiple version files and templates

Extend devflow to support multiple version files of different templates.
To use multiple version files, the user has to define a comma-separated
list of version files and templates in the 'version_file' and
'version_template' options of the configuration file.