use temp filename, not curdir
PEP8
Merge branch 'fix/test-tempfiles' of github.com:ged-lab/khmer into update/sandbox

Conflicts:
	ChangeLog
Merge pull request #710 from ged-lab/fix/test-tempfiles

use temp filename, not curdir
Merge branch 'master' of github.com:ged-lab/khmer into update/sandbox