[Question] Upgrade from Android 4.2.2 to 5.1 on Alcatel One Touch 7041X.

Hello, I want to upgrade the android of my phone from 4.2.2 to 5.1 because I've read that it brings multiaccount function even to phone devices, and I really need it because I have multiple accounts of a game which data is saved on the user itself.

I was multiaccounting on a tablet, but the tablet broke and now I'm using Bluestacks for the other two game accounts which is a really bad alternative (despite that Bluestacks works like x2.5 faster than my phone) specially due those days that I'm out of home.

So, I want to know how can I upgrade from Android 4.2.2 to 5.1?
-My phone device is: Alcatel One Touch 7041X ( http : // www . alcatelonetouch.com/ph/products/andorid_smartphones/one_touch_pop_c7.html#.Vd6mT_RlGUk )
-Current Android version is 4.2.2 (Rooted, using SuperSU, before it had Kinguser which I could replace to SuperSU).
-Kernel Version is 3.4.5 (Not sure if it's necessary to know, anyways I leave it here).
-Compile number is 070FSG1.
-Phone company is: Vodafone ES
-This phone doesn't have guarantee, so I don't mind if upgrading the OS voids it.

Please if possible provide me the link of any guide if is already available (search by device didn't shown any result), files or anything necessary.

Thank you in advance.
EDIT: Also in case of failure please provide me a link of a guide for restore the device.