Initial IMaterialAsset and OgreMaterialAsset implementation.
OgreMateria: Fix warnings and linux build error.
Materials: Implement Mesh component handling asset reference changes. Left few of the Urho related parts open for @cadaver (default empty/error mat apply). New AssetRefListListener: This class moves most of the complexity of managing material requests out of component, atm in particular Mesh. Signals and functions include support for indexes so that the component does not need to loop its local refs all the time to find the correct one. Also beneficial is that the internal state of the list listener can clean and resolve refs without modifying the original Attribute value (hence triggering network change or needs to manage LocalOnly stuff).
Merge remote-tracking branch 'origin/master' into ogre-material
AssetRefListListener: Change API index functionality to be uint. Remove uint to int comparison warnings.
OgreMaterialDefines: Fix a few sloppy bugs that found reading the diffs through.
OgreMaterialDefines: Allow finding newline and } chars directly from the lookup pos (triggered via SkipBlock).
Ogre MaterialParser: Handle empty lines correctly (doh).
Merge remote-tracking branch 'origin/master' into ogre-material
Mesh: Fix atm commented code.
OgreMaterial: Implement helper functions to get typed values out from the raw string representation. These will be helpful when we start applying more than texture ref to the created Urho material.
Ogre Material: Remove redundant .Trimmed(), already done by StringVectorValue().
Ogre Material: Fix StrinValue() to also give possibility to define default value like the other funcs.
AssetRefListListener: Correctly emit Cleared for indexes that were previously non-empty.
Merge pull request #7 from realXtend/ogre-material

Mesh component material impl + IMaterialAsset + OgreMaterialAsset