Code submission - Githubissues

Re: #8

Description: Able to submit passed code

Details:

playground's half containing code editor and test cases should have button: 'Submit'
event listener on 'Submit' button to submit the code
submitted code should be saved (DB or locally??) to appear later when problem is revisited
Upon successful submission, problem should appear to be solved via visual cue (checkmark in the row above problem description)
Update user's data to contain number of passed/failed submissions + completed/unsolved problem
Only visible to authenticated users only

asadsid95 / sme-fe