fix windows build scripts, add windows opus support

inputsystem/wscript

@@ -1,6 +1,7 @@
 #! /usr/bin/env python
 # encoding: utf-8
 
+from gettext import install
 from waflib import Utils
 import os
 
@@ -20,7 +21,8 @@ def build(bld):
 		'joystick_sdl.cpp',
 		'touch_sdl.cpp',
 		'key_translation.cpp',
-		'steamcontroller.cpp'
+		'steamcontroller.cpp',
+		'../public/tier0/memoverride.cpp'
 	]
 
 	if bld.env.DEST_OS == 'win32':
@@ -44,6 +46,15 @@ def build(bld):
 		
 	install_path = bld.env.LIBDIR
 
+	# Copy SDL2 dependency
+	if bld.env.DEST_OS == 'win32':
+		bld(
+			rule='cp ${SRC} ${TGT}',
+			source='../lib/win32/public/'+bld.env.DEST_CPU+'/SDL2.dll',
+			target='SDL2.dll',
+			install_path=install_path,
+		)
+
 	bld.shlib(
 		source   = source,
 		target   = PROJECT_NAME,