Refactor frontend.py (remove duplicate code) #311
This PR is directly inspired by #62.
A little bit of intricate, fine magic is used to create an Optparse parser out of the Distutils commands, a little bit of fine-tuning here and there and then everything . . . just works, with a third less code.
This should do wonders for test coverage statistics, which also means the frontend code will be more easily maintained.
Current coverage is
This is a combination of the test suite improvement fbc1648 and the frontend changes in 414aec5..ee8abd6. * Harmonize extraction keyword parsing between distutils and standalone CLI (python-babel#388, python-babel#384, python-babel#311) * Don't use unicode-variant %r for logging * extract: don't die badly when no input paths are specified in optparse mode * Remind the optparse CLI about `extract -s` (a shorthand for `--strip-comments`) (python-babel#390) * Teach the optparse CLI about the parameter aliases it had forgotten in python-babel#311 (python-babel#390)