has_one and has_many: accept foreign_key option

[tomash]

has_one and has_many macros now honor foreign_key option, if the foreign key name should be different than guessed from class name.

We've stumbled upon this when building a set of Repository classes for existing Mongoid models, which meant we had both DealRepository and Deal classes, the foreign key for them used in child classes is always deal_id, never deal_repository_id.

[coveralls]

Coverage increased (+0.02%) to 98.84% when pulling 123bdd6 on rebased:association-foreign-keys into d5105ad on efreesen:master.

[coveralls]

Coverage increased (+0.02%) to 98.84% when pulling 123bdd6 on rebased:association-foreign-keys into d5105ad on efreesen:master.

[efreesen]

Great

[efreesen]

Pushed version 0.5.1 to rubygems.

Thank you.