Redesign changelog affecting part

[viviag]

Work in progress

Current coverage:

• Refactor eval local function of checkLocalChangelogF.
• Fix bug with ignoring and watching multiple files.
• Use git diff-tree instead of git show as clearer.
• Implement ignored commits (Implement ignored commits #81)
• Ignore changes to changelog itself by default (Ignore changes to changelog itself by default #77).

Further coverage:

• Refactor processChangelog and checkLocalChangelogF. (Refactor changelog checking functions #91) These are shit now.
• Ignore all present changelogs by default for each changelog.
• Make --update-changelog and --bump-versions proper commands #80 - and split further tool into two chained domains. Make list of common options, list of versioning options and list of logging options. Also this will simplify usage reference. As for git with its git checkout etc.
  Generally I tend to develop it more Unix way.

In plans there are also:

• Support multiple target changelogs. #100
• Allow wildcards in filepaths #82 - with _/_ as structure wildcard and __ as complete wildcard
• Add interactive mode #71 - now I little more know what to do, it's breaking change of usability
• Switch to Dhall for configuration file #78 - To be able to split spreading config to couple of files
• Add tests #60. - After I rend all the giants.

After this PR I propose to release 0.3.
After these all it's time to release 1.0.