Try different chaining method

Added MimicFilter which mimics some filter, and can be easily made to
mimic another filter. Using this instead of SourceFitler makes it
possible to easily replace all occurrences of it.

This supersedes the Filter.Append method and all related methods.
Revert "Make LoadSettings(), SaveSettings() abstract."

This reverts commit c5a318ff6ab1f667ff1733aec1e181f7720aeab5.
Merge pull request #20 from Shiandow/master

Merge from Shiandow:master
Merge pull request #21 from Shiandow/work

Work
Merge pull request #22 from zachsaw/work

Merge from Shiandow:work
Renamed MimicFilter to ProxyFilter.
Changed m_Filter var to Filter property.
Merge pull request #23 from zachsaw/work

Refactoring
Attempts to make MyRenderScript.cs simpler and more intuitive.
Changed CreateScripts and GetScriptChain return type to IList<RenderScript>, which will accept any objects that implement IList<RenderScript> (List, Dictionary, array etc.).
Merge pull request #24 from zachsaw/work

Changed CreateScripts and GetScriptChain return type to IList<RenderScri...
Wholesale changes to RenderScript API - must only be used with MPDN v2.11.0 and above.
Manual merge from Shiandow's work branch.
Fixed ScriptChain ConfigDialog UI positioning when resized.
Reformatted ScriptChain to make it inline with coding style of the rest of the scripts.
Minor code reformatting
Quick reformatting for Custom.MyRenderScript.cs.
Updated README.md to include a section on developing / debugging render scripts.
Simplified Custom.MyRenderScript.cs by removing unnecessary readonly keyword.
Added LoadShader to RenderChain.
Modified ShaderCache such that it recompiles shader when its source has been changed.
Merge upstream (Manually)
Merge upstream #2
Merge upstream #2
Merge upstream #3