Remove script generation from docs Makefile.
Remove script generation from docs Makefile.

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