Added HasMany#injectCreator and Model.createAssociatedModel()
Merge branch 'feature/add-association-transaction-support' into feature/create-relation-objects

Conflicts:
	test/associations/has-many.test.js
Merge branch 'feature/add-association-transaction-support' into feature/create-relation-objects
Added transaction support for `.createAssociation`
Merge branch 'bugfix/find-transaction-option' into feature/create-relation-objects
Added `.createAssociation` support for `HasOne` and `BelongsTo`
Merge branch 'master' into feature/create-relation-objects
Merge pull request #1213 from saschagehlich/feature/create-relation-objects

Added HasMany#injectCreator and Model.createAssociatedModel()