Make some adjustments to .summon and .group summon behavior to make them more permissive:

- Now only requires the either target's group leader or target itself to be on your map
- Now summons all applicable group members even if one member fails checks
- No longer has some truly weird edge case instance unbind code that could cause exploit behavior (Really, I have no idea why this existed, because it certainly didn't do what it might've been meant to do.)

sql/updates/world/3.3.5/2017_06_12_00_world.sql

@@ -0,0 +1,5 @@
+-- 
+UPDATE `trinity_string` SET `content_default`="You can only summon a player to your instance if either that player or his group leader is in your instance, too." WHERE `entry`=103;
+DELETE FROM `trinity_string` WHERE `entry`=187;
+INSERT INTO `trinity_string` (`entry`,`content_default`) VALUES
+  (187, "The group's leader is not in your instance - summoning only members that are already in your map.");