Move from using ActiveRecord to using Mongo Mapper and Postgresql to MongoDB.

config/application.rb has been modified to include specific rails modules rather than all to “remove” active record.

Previously, the “fields” for the model objects where describe in database terms in schema.rb.   Now the model object classes describe their fields.

In the view “fields_for ”  elements now are provided with the model “sub object” as well as its key. This seems to be required as “fields_for” forms works with active record without this but mongo mapper is not providing equivalent model information.
Add exodus mongo mapper database migration utility and mongo configuration.

Added:
mongo_config.rb to construct the database name from the environment
mongo.yml to configure mongo mapper
20140913134000_mongo_add_admin_user.rb to initials the database with the admin user

Removed:
schema.rb which no longer required
database.yml which is no longer required

Modified:
Gemfile to add exodus
Rakefile to require the project environment - this was required as the exodus configuration was not environment aware and to minimise duplication, the mongo mapper configuration is used to configure exodus.