premake5: Map "Debug" and "Release" configurations to "Normal".

The general standard for any C++ project normally is to have a Debug and a Release version of the binaries, however in our case we only have one configuration that mixes both. Setting up aliases for this in order to prevent confusion on why the standard configurations don't work.

premake5.lua

@@ -48,7 +48,7 @@ newaction {
 
 solution "iw4x"
 	location ("./build")
-	configurations { "Normal" }
+	configurations { "Normal", "Debug", "Release" }
 
 	project "iw4x"
 		kind "SharedLib"
@@ -56,6 +56,10 @@ solution "iw4x"
 		files { "./src/**.hpp", "./src/**.cpp" }
 		includedirs { "%{prj.location}" }
 		architecture "x32"
+		configmap {
+			["Debug"] = "Normal",
+			["Release"] = "Normal"
+		}
 
 		-- Allow newer Microsoft toolsets but fall back to VS2013
 		if _ACTION == "vs2015" then