Removed #method_missing from Fog::Model

Since #74 is merged, we dont need to create acessors to the aliases anymore.
Merge pull request #75 from zertico/remove_method_missing

Removed #method_missing from Fog::Model
Added Rubocop

The HashSyntax cop is turned off since we still support ruby 1.8.7
Fix build on ruby 1.8.7 and 1.9.2
Fixed method calls using ::
Using && instead of and
Merge pull request #76 from zertico/rubocop

Added Rubocop