Using two stage install (--foreign) in cdebootstrap

For the feature "install in internal storage" we can't debootstrap debian on /data/debain as its mounted with nodev parameter.
To skip nodev check we are using two stage installer.
Adding feature of installing Debian in /data/debian location directly without creating img file

* Modifying the shell scripts
* adding option in the Preference
* adding NativeHelper.isInstalled() function
* updating the media mounted and unmounted Receiver
moving to cdebootstrap v0.6.2 from v0.6.1