added overloaded loadProjectionMatrix with viewportRect argument
added overloaded loadProjectionMatrix with viewportRect argument
added setter for Intrinsics::imageSize
also use viewport width/height for frustum computation for consistency.
(has to be equal to imageSize to get the principalPoint right anyway)
fixed whitespace
replaced viewport rectangle by a position offset to simplify client apps
Merge pull request #93 from kikko/master

overloaded Intrinsics::loadProjectionMatrix with viewportRect argument