[0383] Added missing gossip menu to 400+ creatures

* Added gossip menus to the following creatures based on YTDB data,
also fixed npcflag when needed. Gossips were checked to prevent linking
to a TBC/WotLK gossip
* Removed unneeded npc_gossips for these NPCs
* When missing, backported related gossip_menu, gossip_menu_option,
dbscripts_on_gossip, npc_text, conditions. This should greatly decrease
the number of broken quests, events or scripts due to missing gossip
menus. Especially for trainers, battleground masters and battlegrounds
emissaries. This also closes #160 and closes #130 and closes #52
  Source: YTDB
[0384] Removed spawn of creature 575 in Scarlet Monastery

* Removed spawns of creature 575 (Fire Elemental) in Scarlet Monastery
because they are summoned
[0385] Fixed groups and patrol of creature 15977 in Naxxramas

* Fixed groups and patrol of creature 15977 (Poisonous Skitter) in
Naxxramas Spider Quarter
* Updated speed of creature 15977 as they should move much faster than
speed = 1
* Adjusted groups of creatures 15977 because in Classic they were
spread differently than in WotLK. They had their own group of 10
spawns: 2 static groups in the first room, one patrolling group in the
first room and in corridor leading to Anub'Rehkan. Current spawns
spread across other mobs groups were used.
Sources:
http://www.youtube.com/watch?v=IbRODBLeqk4
http://www.youtube.com/watch?v=agWfYn0piY8
http://www.youtube.com/watch?v=YtLkzm3eELs
http://www.youtube.com/watch?v=iA_de7CcIrQ
This closes #101