Massive refactoring of all code + audio skeleton.

This should make it easier to find files and (in the future) split things
up into separate libraries.
It also changes around emulator initialization to make it a little more
difficult to do things out of order and a little more sensible as to when
real init work happens.
Also adding a skeleton audio system/driver and reworking CPU register
access to be more extensible.

src/xenia/kernel/sources.gypi

@@ -1,22 +1,19 @@
 # Copyright 2013 Ben Vanik. All Rights Reserved.
 {
   'sources': [
-    'export.cc',
-    'export.h',
     'kernel.h',
     'kernel_module.cc',
     'kernel_module.h',
-    'runtime.cc',
-    'runtime.h',
+    'modules.h',
     'shim_utils.h',
-    'xbox.h',
     'xex2.cc',
     'xex2.h',
     'xex2_info.h',
   ],
 
   'includes': [
-    'modules/sources.gypi',
+    'xam/sources.gypi',
+    'xboxkrnl/sources.gypi',
     'util/sources.gypi',
   ],
 }