1.10.1 changes (Iriel)

Upcoming 1.10.1 changes

 * Updated CheckBox:SetCheckedTexture to accept a texture object like the other texture functions.
 * Slider:SetThumbTexture(Texture or "texturePath")
 * Fixed overall script memory usage increase in 1.10.
 * Skip UTF-8 byte-order marker at the start of .toc files.
 * Added Lua collectgarbage function.
 * Fixed CastSpellByName and pet spells when pet is not available (Behaves like 1.9 rather than failing with unknown spell error)