That way, we will try to decode as default encoding (usually
utf-8), but allow ourselves to simply keep bytes that don't
match within the resulting unicode string.

That way, we allow for lossless decode/encode cycles while still
assuring that decoding never fails.

NOTE: I was too lazy to create a test that would verify it, but manually
executed https://github.com/petertodd/gitpython-unicode-error.

fixes #532

+ Mark all unused vars and other non-pep8  (PyDev) warnings
+ test_utils:
  + enable & fix forgotten IterableList looped path.
  + unittestize all assertions.
+ remote: minor fix progress dispatching unknown err-lines