assets/js/vendor/backbone-relational.js
function( options ) {
			this.acquire(); // Setting up relations often also involve calls to 'set', and we only want to enter this function once
			this._relations = {};

			_.each( _.result( this, 'relations' ) || [], function( rel ) {
				Backbone.Relational.store.initializeRelation( this, rel, options );
			}, this );

			this._isInitialized = true;
			this.release();
			this.processQueue();
		}
function( options ) {
			this.acquire(); // Setting up relations often also involve calls to 'set', and we only want to enter this function once
			this._relations = {};

			_.each( _.result( this, 'relations' ) || [], function( rel ) {
				Backbone.Relational.store.initializeRelation( this, rel, options );
			}, this );

			this._isInitialized = true;
			this.release();
			this.processQueue();
		}
Initialize Relations present in this.relations; determine the type (HasOne/HasMany), then creates a new instance.
Invoked in the first call so 'set' (which is made from the Backbone.Model constructor).