reformat README.md
test that applied patch can be committed
TODO items
add usage message to bin/git-splitpatch
tests for chunk descriptor formats
write_chunk now includes a fake header in each file

Also write_chunk renamed to write_chnuk_file
parameterize patch file used for patch parsing testing
set up parsepatch t.dat dir; add a loc-less test patch
bug fix in Patch::Chunk->descriptor
Merge branch 'splitpatch' into commit

Conflicts:
	.what
	TODO
correct bad expected test output