New Features
* Implemented new `field` command to return a single value.
Requested by navidcity in 19.
* Updated documentation:
* Restructured sections
* Added lots of doc-strings.
* Listed supported CI services / platforms.
* Listed supported VCS.
* Listed supported languages (all).
* Auto document command line interface from ArgParse configuration (autoprogram).
* Listed C example.
* Added new `VersioningException` and `ToolException`.
Changes
* Bumped dependencies.
* Improved exception messages.
* Renamed `GitHelper` to `GitHelperMixin`.
* Updated list of dependencies.
* Updated installation instructions.
* Included instructions on how to run unit tests, code coverage and type checking.
* Refactored configuration classes from nested classes to normal classes in a module.
Bug Fixes
* Fixed testcases.
Related issues:
* Closes 19
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/cc navidcity