abstract model - setting resources made consistent

...with setting resource_name
abstract model - support for instantiating subclasses
simple crud controller - support for custom as_json options
comp. res. - api, model for each provider
cli - case insensitive choices for optparse options
comp. res. cli - actions list and info
comp. res. cli - create
comp. res. cli - updating
comp. res. cli - deleting
comp. res. - system tests
comp. res. cli - pylint fixes
foreman_api gem version bumped up to 0.0.10
Merge pull request #1363 from tstrachota/compres

Compute resources API & CLI