Adds a zoom palette to Color My World Activity

[SamarthBagga]

Fixes #1593
Added a zoom palette to the Color My World Activity similar to that in the Caligra Activity.

Demo -

screen-capture.19.webm

[llaske]

Good job.
Miss the update of the tutorial to add explanation of the new palette.

[SamarthBagga]

@llaske, Apologies for the oversight, I have added the tutorial for the zoom palette. I have added translations for the languages that had translated tutorial strings, the languages that did not have translations for the tutorial strings, I have left them in english for now.

[llaske]

Nice thanks.

I have added translations for the languages that had translated tutorial strings, the languages that did not have translations for the tutorial strings, I have left them in english for now.

That's what should be done. We're expecting localization by native people instead of using Google translate.

If slightly update the string: the word "palette" is not necessarily known by users and it's better to talk about "map".