Insertion sort in C++

[deepanjali19]

I will add the code for insertion sort implementation in C++.

Am I working on this? - Yes

I will be making a pull request in couple of days.

[GnikDroy]

Thank you for taking an interest in the project. Make sure to read the CONTRIBUTING file before issuing a new PR.

[Vipulsh]

Is this issue still open and need to worked by someone?