Merge pull request #1 from zachsaw/master

Update from original
Improved Texture Allocation #2

Instead of reusing textures by saving a reference to the Texture itself we now save a reference to the Filter that owns this texture.

This is necessary to be able to reuse InputRenderTarget and OutputRenderTarget since those textures can be replaced at any time by MPDN, without updating the references in the filters that reused them.
Allocate textues in GetFrame()
Removed AllocateTextures()
Removed AllocateTextures from On***SizeChanged.
Merge pull request #2 from Shiandow/master

Oops
Remove AllocateTexture in SetupRenderChain

Almost forgot that one.
Earlier bug-fix is now somewhat unnecessary.
Merge pull request #5 from Shiandow/patch-1

Improved Texture Allocation #2