Added contributors to README.textile.
Fixes Druid HotW aura. Issue #25

HotW Buff Aura matches spellbook id. It is, however, different for each
spec.
Druid: revision bump.
Copyright update.
Druid: also map the Heart of the Wild buffs to the talent.
Core: track spell sources.

This allows to easily get version information about a spell.
Warrior: added Glyph of Incite.

Fixed GH-24.
Fixed indent in Warrior.lua.
Warlock: added Rain of fire (closes GH-27) and Burning Rush (closes GH-26).
DK: added Presences.

Fixes Adirelle/AdiButtonAuras#32.