Add 'M2' device assertion

[Ant95]

Just had this case problem to flash this rom on a Meizu M2 (mini). The device was identified as "M2" and not "m2".
Not sure if it's the right file to edit to fix the problem as I don't have the required env to build and test it.
Anyway to fix my problem I had to edit this file in the zip: "./META-INF/com/google/android/updater-script".

[divis1969]

Yeah, this is the right file.
Meantime the problem is that recovery (or maybe ROM) creators does not follow any convention and are inventing new identifiers.
I will include this patch into the next release, but this can be easily broken by new recovery...
BTW, which recovery was in use when you encounter the issue?

[Ant95]

Ok, I didn't know that the device identifier was defined by the recovery itself.
I was using a TWRP 3.0 recovery downloaded at: https://drive.google.com/open?id=0ByjTaBzI678NQTBZaTFkNlVYYU0
(Link source: http://www.theverdict.in/how-tos/updated-twrp-3-0-recovery-meizu-m2/)

BTW, I wanted to thank you for your work, everything works fine for now :)