Updated build objects directory to use same pattern as libraries.

build/Helpers.lua

@@ -14,6 +14,7 @@ if _ARGS[1] then
     builddir = path.getabsolute("./" .. _ARGS[1]);
 end
 
+objsdir = path.join(builddir, "obj", "%{cfg.buildcfg}_%{cfg.platform}");
 libdir = path.join(builddir, "lib", "%{cfg.buildcfg}_%{cfg.platform}");
 gendir = path.join(builddir, "gen");
 

build/premake4.lua

@@ -16,7 +16,7 @@ solution "CppSharp"
   flags { common_flags }
   
   location (builddir)
-  objdir (path.join(builddir, "obj"))
+  objdir (objsdir)
   targetdir (libdir)
   debugdir (bindir)