Delete unnecessary branches

[ratanparai]

I'm submitting a...

[ ] Bug report  
[ ] Performance issue
[ ] Feature request
[ ] Documentation issue or request
[x] Other... Please describe:

Current behavior

There are lot of unnecessary branches.

Expected behavior

Every PR should be from different branch and after Merging the PR you should delete that branch. To do so click the Delete branch button.

Example -
Go to PR #18 and see there is a button named Delete branch before the comment box in the bottom. you should press this button every time you merge PR.

What is the motivation / use case for changing the behavior?

Unnecessary information is evil. If changes from any branch is already merged to the master bannch then there is no need for the branch to exists. So delete it and save the world

[aftabkajal]

Delete done unnecessary Branch. close #20