capture stderr messages from khmer/file.py errors
Merge remote-tracking branch 'origin' into cleanup/filepy2
updated ChangeLog for test_script_arguments.py mods
Merge remote-tracking branch 'origin' into cleanup/filepy2

Conflicts:
	ChangeLog
Merge branch 'master' of github.com:ged-lab/khmer into cleanup/filepy2
Merge remote-tracking branch 'origin' into cleanup/filepy2

Conflicts:
	ChangeLog
Merge pull request #487 from ged-lab/cleanup/filepy2

capture stderr messages from khmer/file.py errors