Move VSFilter and BaseClasses VS2012 project files to their own folders
Add XySubFilter build for VS2012
Fix the following problems:
Compilation problems in VS2012 debug builds
Compilation of log4cplus in VS2012 properly (https://github.com/wilx/log4cplus-trunk/commit/9a368665300bc095dcd3507d4426c5e21f35078d)
Project filters descriptions consistently
Added the small necessary changes to the VS2012 projects
Integrate VS2012 build into build_vsfilter.sh to avoid code duplication

Fix "-projects" switch not being parsed.
Change "-projects" to "-proj" in usage text and add VS2012 usage.