Adds `hfs-wholefile` to `cascalog-more-taps`.

This work has originally been done by Sam Ritchie for reddmetrics/forma-clj.
I just imported it into the cascalog-more-tabs subproject, and added some tests.

Note that the original reddmetrics/forma-clj repo is under Eclipse Public License - Version 1.0
while this cascalog repo is under Apache License, Version 2.0.
This should [not](http://www.tldrlegal.com/compare?a=Apache+License+2.0+\(Apache-2.0\)&b=Eclipse+Public+License+1.0+\(EPL-1.0\)) not be a problem, especially when considering that @sritchie is the original author.