adding partitions

Adding these partitions to enhance ROM2SD/DATA2SD 

-This will make it possible to format external /data to both ext4 & f2fs from within TWRP
-The will let you also format external /system from within TWRP
-The labeling of said partitions are as follows
-mmcblk1 = ext partition #1 end-users storage space
-mmcblk2 = ext partition #2 /data
-mmcblk3 = ext partition #3 /system