Compatibility OGRE 1.10/Removed unnecessary deps

Changed StringUtil::BLANK to an empty string, added ifdefs for Xalafu
compatibility and added some include files for classes that were only
forward declared but never included. (Wouldn't compile on VS2013)
Removed unnecessary conditionals

Fixing the previous commit (981a3ea).
Merge pull request #9 from MindCalamity/master

Compatibility OGRE 1.10/Removed unnecessary deps