changed order in deploy and javascript path

compiled js lives in public/static
we need to first compile it and then touch it during the finalize_update step.
get rid of RAILS_ENV it's Rails.env now.
stop using RAILS_ROOT - use Rails.root and real pathnames instead
set default for info level without overwriting a constant

DEFAULT_INFO_LEVEL is already set on loading /lib/crabgrass/info
fixed search filter path to work with PathName

and two minor style fixes
use the more convinient + instead of PathName.join
Merge pull request #44 from Crabgrass/bugfix/4181-deploy-to-staging-causes-errors

Bugfix/4181 deploy to staging causes errors