remove #include <stdbool.h> it breaks MSVC 2010

enable gtest by default when using premake, added flag without-gtest
use gtest ASSERT_EQ( expected_value, actual_value) instead of the reverse,
this fixes issue 205 (https://github.com/bulletphysics/bullet3/issues/205)

btgui/urdf/boost_replacement/string_split.cpp

@@ -1,7 +1,7 @@
 
 
 #include <assert.h>
-#include <stdbool.h>
+//#include <stdbool.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>