one-step project creation with mortar new or mortar projects:create
unit test for one-step project creation
Move new back to an alias for generate:project
Make projects:create leave you in the projects directory, so that commands actually work when you run them
Factor git check into common method
Provide better error messages from register when the project already exists or we're in the parent directory instead of the project directory, and alias 'mortar register' to 'mortar projects:register'
Merge pull request #48 from mortardata/jpacker_one_step_project_creation

Improve mortar projects:create and mortar projects:register commands