Initial commit

added libraries:
opus
flac
libsndfile

updated:
libvorbis
libogg
openal

- Everything works as expected for now. Bare in mind libsndfile needed the check for whether or not it could find the xiph libraries removed in order for this to work.

Engine/lib/libsndfile/docs/win32.md

@@ -0,0 +1,18 @@
+---
+layout: page
+---
+
+# Building libsndfile on Win32
+
+**Note : For pre-compiled binaries for windows, both for win32 and win64, see
+the main web page.**
+
+There are currently two build systems; the official GNU autotool based one and
+a more limited and experimental CMake based build system.
+
+libsndfile is written to be compiled by a compiler which supports large chunks
+of the 1999 ISO C Standard (tested with GCC, Clang and Visual Studio 2015).
+
+It is recommended to use CMake and Visual Studio to build libsndfile on Windows
+but you can try the [MinGW](http://www.mingw.org/) compiler suite with Autotools
+or CMake buildsystem.