add instructions to checklist in PR template
as new devs creating PRs seem to have trouble
formatting their code, creating a single commit, adding tests, running
their changes and tests through the build process I
* tried to clarify the language/structure of the PR template
* added instructions to the checklist so that if a new devs has doubts
directly has the right resource at hand to check the box in the end
djazayeri Automatically assigned
Daniel Kayiwa Automatically assigned