Move canon specific material to canon.py module.
Have basic implementation for get and set methods and have method to list all properties.
Added take_exposure method.  Tested with Canon 6D.
Working on getting filename info from camera configuration.  Not working yet.
Specify filename for image capture using photo.  Still need to write method to generate filename from pattern in config file.
Adding environment for cloud senser
Merge branch 'camera' into develop

Conflicts:
	panoptes/camera/camera.py
	panoptes/observatory.py