Generate C file / header for svn version string

Generate C file / header for svn version string

It's now easier to force rebuild of files depending on the svn revision

version.c/version.h are generated once with new tools/genversion.sh
Changes in the VCS are still not auto detected, so you'll have to remove
builddir/version.* if you want to change the string in your binaries

APPSVERSION is now called RBVERSION and is defined in the generated
header instead of being defined by the Makefiles
appsversion is now called rbversion (the plugin api number didn't change
since old modules are still binary compatible)

Change some bootloaders to use knwon-at-buildtime RBVERSION instead of
"%s" + rbversion

You'll need to run make clean to regenerate dependencies after the
removal of apps/version.h

To build binaries with a different version string, hand-edit
tools/version.sh or tools/genversion.sh (which calls the former)

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@26320 a1c6a512-1295-4272-9138-f99709370657