More Updates

Image Chopper properly changes import settings on source images, and has
proper conditional compiliation.

Fixed a bug with MaterialPanner.
Added some documentation to BoundsF, DataF.
Makes List<T>.ToStringArray() actually return an array, instead of a
list. Moved list returning function to List<T>.ToStringList()

Adds float.Clamp(Vector2) - clamp a float between the two values in a
Vector2
Adds string.PreviousDirectory() - get the string representing the folder
above

Adds Vector3.GetBytes(), Vector3.Floor()