Automatically discover the latest and greatest version of the Android SDK and
NDK by fetching it from the index.
git-svn-id: svn://svn.rockbox.org/rockbox/trunk@30334 a1c6a512-1295-4272-9138-f99709370657
Update the download URLs to the most recent versions of SDK and NDK, the
previously used r09 of the SDK isn't available at that location anymore, and
differentiate between host platforms.
Note: while the script now can install the toolchain on Cygwin building for
Android on Cygwin does not work.
git-svn-id: svn://svn.rockbox.org/rockbox/trunk@29993 a1c6a512-1295-4272-9138-f99709370657
