Add functions for adding titles to dtypes and for getting the title for a field from an array.
Add functions for adding titles to dtypes and for getting the title for a field from an array.

git-svn-id: acf0ef94bfce630b1a882387fc03ab8593ec6522@155 150532fb-1d5b-0410-a8ab-efec50f980d4

dopplershift/MetPy,ahill818/MetPy,Unidata/MetPy,ShawnMurd/MetPy,ahaberlie/MetPy,jrleeman/MetPy,dopplershift/MetPy,deeplycloudy/MetPy,ahaberlie/MetPy,Unidata/MetPy,jrleeman/MetPy