adding simple ping endpoint
Merge branch 'develop' of github.com:osmlab/maproulette into develop

# By Serge Wroclawski
# Via Serge Wroclawski
* 'develop' of github.com:osmlab/maproulette:
Adding a /me endpoint to the api
Adding OK button to welcome
adding ping endpoint
vastly improving task poster example
Merge branch 'develop' of github.com:osmlab/maproulette into develop

# By Serge Wroclawski
# Via Serge Wroclawski
* 'develop' of github.com:osmlab/maproulette:
  Adding a /me endpoint to the api
  Adding OK button to welcome

Conflicts:
	maproulette/api/__init__.py