Added control structures concept for powershell

[ulyssear]

What GitHub issue does this PR apply to?

Resolves #698

What changed and why?

Added control structures, the second added concept for Powershell

(If editing Django app) Please add screenshots

No screenshot is necessary.

Checklist

• I claimed any associated issue(s) and they are not someone else's
• I have looked at documentation to ensure I made any revisions correctly
• I tested my changes locally to ensure they work
• (If editing Django) I have added or edited any appropriate unit tests for my changes

Any additional comments or things to be aware of while reviewing?

Is it possible to have the "hacktoberfest-accepted" label for this pull request ?

[geekygirlsarah]

A few minor changes and this is probably good to go

[geekygirlsarah]

Thanks for the update. I can merge it in! Happy Hacktoberfest (for a few more hours anyway)!