Added Umbral Creation to the game.
Some changes to achievements_lib.lua

New file: data/npc/scripts/Eruaran.lua

Added Umbral Creation almost 100% like Tibia RL. (The chances for creating/improvement/transforming are not the same. Should be updated)
Umbral Creation was created following the info found at http://tibia.wikia.com/wiki/Umbral_Creation
The weapons and items required are the same as Tibia RL.
NPC Transcripts are not 100% like Tibia RL. Also there are some keywords that doesn't have response. I didn't added them because i couldn't find the real transcripts.

To be added: Umbral-Achievements
Some scripts converted to meta.
Fixed function playerExists in customfunctions.lua. It was always returning true.
Fixed a bug with a nil variable
Added a new creaturescript. This new script will work with the 'onKill' event and will support misc kills (Bosses, creatures quantity, etc). It is registered with the name of 'MiscKill'
Added the following achievements to the game:

Askarak Nemesis (Obtained when killing 100 Askarak Prince)
Back from the Dead (Obtained when slaying Zanakeph)
Back into the Abyss (Obtained when slaying Thul)
Bibby's Bloodbath (Obtained when slaying Bibby Bloodbath)
Blood-Red Snapper (Obtained when slaying The Snapper)
Choking on Her Venom (Obtained when slaying The Old Widow)
Cocoon of Doom (Obtained when slaying Bloom of Doom) [Note: Slaying or dealing damage? Idk if that creature can be killed]
Crawling Death (Obtained when slaying Fleshcrawler
Death Song (Obtained when killing 300 Deepling Spellsingers)
Deer Hunt (Obtained when killing 400 White Deers)

Note that the achievements were added following the description found at www.tibia.wikia.com
More achievements will be added eventually.
Revert "Some scripts converted to meta."

This reverts commit 1febb64a0475eaec9aefe7c50a76d2c046df126c.
Merge pull request #1014 from edumntg/master

Added Umbral Creation to the game.