implement dropbox deployer and basic test
set proper dropbox target default. clean up dropbox.destroy
Merge branch 'master' into dropbox

Conflicts:
	lib/commands/default.coffee
	lib/deployers/deployer.coffee
	lib/deployers/dropbox/index.coffee
	lib/deployers/heroku/index.coffee
	lib/deployers/s3/index.coffee
	package.json
	test/test.coffee
Merge branch 'master' of github.com:HHSnopek/ship