Merge pull request #7 from zachsaw/work

Cumulative changes from work branch.
Merge pull request #8 from zachsaw/work

Added linear light scaling capabilities
We should allocate new textures if the filter changed
Merge pull request #9 from Shiandow/patch-1

We should allocate new textures if the filter changed
Fixed filter not updated when settings changed
Merge pull request #12 from zachsaw/work

Fixed filter not updated when settings changed
Changed NEDI to specify original video size when UseNedi is false. Reverted NeedToUpscale to back to checking Video and Target sizes. Bug reported here: http://forum.doom9.org/showthread.php?p=1699383#post1699383
Updated README.md
Write your own render script chain as a render script (requires MPDN v2.9.3 and above)
Removed debug line in Filter.cs
SourceFilter is replaceable when Append is called.
BaseSourceFilter is thus introduced for derivation purposes.
Added Nedi quadrupling in MyRenderScript.cs example.
Fixed IsDownscalingFrom/IsNotScalingFrom/IsUpscalingFrom methods.
Changed MyRenderScript.cs example to upscale using NEDI once only by default (with instructions to enable stacking NEDI until past target size).
Removed unused namespaces.
Updated comments in MyRenderScript.cs example (to improve clarity)
Refactored DeepCloneFilter method to reduce code (with speed up bonus)
Improve shader

Correct chroma offset
Pull Zachsaw/work