add button to download/save the meme

[dev-lovedeep]

This issue is currently assigned to @codechampriyanshu

[geeqib23]

I am requesting to solve this issue on Contrihub but it tells me "Assignment Request for Issue #9 of Meme-Generator cannot be made by you currently." even though the issue is open and non-restricted.

[DuP-491]

@geeqib23 you must have already 2 issues at hand