Add "first": a script to find the git commit that introduced a feature.

Takes a required argument that returns 0 if the feature is present.
e.g. rgrep newsymbol srcdir.
Merge branch 'master' of github.com:mikelward/scripts
Merge branch 'master' of github.com:mikelward/scripts
Rename desc to he.  Remove LANG and col workarounds.  Don't use a pager.
Merge branch 'master' of github.com:mikelward/scripts