installer: Allow host-bin restoration only.
mkpart.sh: Create a separate partition for crouton.

Prevents accidental wiping when switching between normal and dev modes.
installer, host-bin: Automatically mount crouton partition.
mkpart.sh: Warn if ChrUbuntu is installed. Increase logout timeout.

Thanks @DennisLfromGA for testing
mkpart.sh: Check if chroots are mounted before waiting 10 seconds.

Also readlink /var/run/crouton (on most recent Chromium OS we use
/run/crouton)
We are crouton Authors...

...crunchy and yummy!
mkpart.sh: Use partx instead of partprobe.

partprobe was removed from upstream (crbug.com/377052)
Merge branch 'separate_partition' of github.com:drinkcat/chroagh