Issue #309: Simplify kallithea.tests.vcs by avoiding unnecessary metaprogramming constructs (conservancy/kallithea)

[Branko Majic]

New issue 309: Simplify kallithea.tests.vcs by avoiding unnecessary metaprogramming constructs
https://bitbucket.org/conservancy/kallithea/issues/309/simplify-kallitheatestsvcs-by-avoiding

Branko Majic:

Current test implementation in `kallithea.tests.vcs` module uses a number of metaprogramming constructs which possibly introduce more complexity than necessary.

For example, a number of test classes are instantiated by using `globals` and `type` construct.

It would be simpler to use plain inheritance instead, if possible - this would still allow for code de-duplication, but would make it clearer without digging into the code on what tests will be run.