Add Inkscape's Zoom

[Fatih20]

Continues upon #467

This is how the icons look under elementary's light theme

This is how the icons look under elementary's dark theme

[cassidyjames]

Is there a reason we're not symlinking to an existing zoom icon? I am also concerned about the similarities between zoom and search here.

[Fatih20]

Is there a reason we're not symlinking to an existing zoom icon? I am also concerned about the similarities between zoom and search here.

Is there any other zoom icon other than the one with white square? Sorry if I'm not being thorough.
I was basing my design in the context of Inkscape. Which, because of the icon placement probably wouldn't be mistaken for search. However, I think zoom is already synonymous with magnifying glasses (unfortunately, so does search which created the problem you've pointed out), that making the design something else would be weird, no?

[jeremypw]

@cassidyjames This review seems to have stalled - should it be closed?