Support the select operation

The selection operation looks like " cond ? value0 : value1; "
Now use the select operation in KSC
Fix the ray transformation issue.
Improve the KSL code

Improve the KSL code for ray-tri intersection
Fix the bug about animated mesh
Add the magic type_n:)

as well as some minor improvement
Add the swizzle utility function
Some improvements about KSC
Get the correct CPU info