lalapps/src/pulsar: move SFTclean from Hough to SFTTools
As discussed on the pulgroup mailing list:
lalapps/src/pulsar: move SFTclean from Hough to SFTTools
-not a pipeline-specific tool
-cleaned up Makefile and .gitignore
@karl-wette I suggest leaving this open until next Wednesday's telecon update just to make sure there are no objections.