Initial per-sample line filtering.
Improved samp filter performance, allow invert.
Args can be provided all at once or in sequence.

The latter style (filt3) allows semi-interactive at Python prompt.
Reduced amount of sample filter code in parser.
Actually write out sample-filtered file.
Switched Writer \r\n to os.linesep.
Fixed sample name list update/printing.
Moved all sample filtering to filter script.
Implemented argparse.
Tweak args, pep8, move empty outfile warning.
Fixed argparse arg names.
Changed default out to sys.stdout
Added unit test for sample filtering script.
Added authorship statement.
Added sample filter to list of scripts in setup.
Moved sample filter object to src dir.
Using logging for easy quiet mode.
Unit test for sample filter module.
Docs/test for undo_monkey_patch
Changed tests to use subprocess returncode.