VS2013, modifications to compile as  C++ and on Windows .
Exception calling: g_hash_table_destroy(im->rrd_map)
temporary commented out
vcxproj: adjusted for debug
use of g_free() cause heap damage on windows if memory is allocated by malloc(). Key is allocated by malloc() in sprintf_alloc(), so free() should use.
Merge pull request #529 from petgit/VS2013

Visual Studio 2013 Support