describe purpose of common directory


git-svn-id: svn://svn.rockbox.org/rockbox/trunk@552 a1c6a512-1295-4272-9138-f99709370657
diff --git a/uisimulator/common/README b/uisimulator/common/README
new file mode 100644
index 0000000..6f920cf
--- /dev/null
+++ b/uisimulator/common/README
@@ -0,0 +1,13 @@
+               __________               __   ___.
+     Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
+     Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
+     Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
+     Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
+                       \/            \/     \/    \/            \/
+
+This directory is for code that is shared between all versions of the
+simulator, but is not needed for the target device.
+
+The first code is for the software mpeg audio decoder.  The actual
+mpeg decoding code is here and the O/S specific sound drivers should
+be located in the x11 and win32 directories as appropriate.