Encryption: needed changes to allow encryption of data partition

1) cryptfs.c requires fstab be named fstab.${ro.hardware}
2) include encyptable parameter on /data in fstab
3) formatting /data in recovery leaves 16kb trailing
4) fstab files cleanup and Readme update

Change-Id: I766d2f3069e9da0a9234c9777de7c18d61428ffd