DFP cant work without the token module

The token module is optional (and should be) but if you dont use it, DFP cant work properly because there is no good way (without writing an alter hook) to get the network id into the ad tag pattern. To resolve:

• network_id should be included in the ad tag pattern automatically
• an update hook should be created in case sites already have the network_id token at the beginning of the ad pattern
• the description of the ad pattern form element should be adjusted
• a message encouraging the installation of Token should be added to the targeting form