adding short versions of flags
Merge pull request #126 from shatterednirvana/with-short-flags

Adding short versions of flags
crashing if both --appengine and --autoscale are used, and setting their defaults properly if only one is set
Merge pull request #127 from shatterednirvana/appengine-autoscale-exclusive

Crashing if both --appengine and --autoscale are used