Experimental support in the collada loader for assigning textures to multiple sets of texture coordinates

Conflicts:
	examples/js/loaders/ColladaLoader.js
Add support for both transparent modes in the collada loader
fixes  an error in a for loop variable that had a wide variety of undesired side effects
Add transparency/alpha fix

Original SHA
81e6267c1384cf25eee94c30678a84a238597ba9
Apply fixes

f9a0b0d80c019e07b10dabac1935b1997a197e6a
Set opacity properly if opacity is 0

0372e95608c5a5672f9f82c6008e092da7cbda54
Add handler for specularLevel

e04f66754e20182c0ff7628d805ec44120aad4a4
Fixed conditional

5e82864ced758c568588833969f281f99cdb1549