Handle missing arguments for phoenix.new mix task
The task was only matching when users passed 0 or 2 arguments. If a
user were to pass only 1 argument, for example the app name, the task would
throw an error. This edit fixes the bug, now it will display
instructions anytime a user misuses the tasks.
Merge branch 'mix_new' of github.com:guillec/phoenix into guillec-mix_new
Merge branch 'guillec-mix_new'