Add new URLs to mapping in globals.js
Add Target Gene link processing for fly and worm

Initial working implementation. Will try a more elegant method next.
Updated code to generate Target Gene link

Fly and Worm now share code to generate the Target Gene link. Human and mouse unchanged.
Add a fly target to test set
Merge 'origin/master' to this branch

Conflicts:
	src/encoded/tests/data/inserts/target.json
Merge pull request #419 from ENCODE-DCC/1758-fly_worm_target_linkouts

1758 fly worm target linkouts