Google Play Music and the tiny internal sdcard: move the cache

OK, so installed Google Play Music, and ran out of flash space instantly.

Solution:

# mkdir -p /mnt/sdcard/gpsflash/MusicCache
# cd /data/data/com.google.android.music
# rm -r cache/*
# rm -r files/*
# mount -o bind /mnt/sdcard/gpsflash/MusicCache cache
# mount -o bind /mnt/sdcard/gpsflash/MusicCache files

and boom, we are good. Now just put these last two lines in a script that runs on startup (see e.g. ScriptRunner etc)