Add Visual Studio 2013 project files.

There is an issue with libSBRenc and libSBRdec as they both contain
several files with the same name. To rectify this libSBRdec's sbr_ram
and sbr_rom had their output obj files renamed to avoid linking clashes.
Also both libs required speciall include directives so as not to get the
identically named include files from the other lib confused.