Add T1 Etudes, update etude.lua to add proper effects

Added T1 Etudes for BRD, powers sourced via bg wiki. 

Tier 1 Etudes
Combined Skill Range	Bonus
≤181 Skill	+3 Attribute
182~235 Skill	+4 Attribute
236~288 Skill	+5 Attribute
289~342 Skill	+6 Attribute
343~396 Skill	+7 Attribute
397~449 Skill	+8 Attribute
≥450 Skill	+9 Attribute

http://www.bg-wiki.com/bg/Etude