PULL_REQUEST_TEMPLATE file

[matrixik]

I would like to add file PULL_REQUEST_TEMPLATE to repo:

Please check if what you want to add to `awesome-go` list meets 
[quality standards](https://github.com/avelino/awesome-go/blob/master/CONTRIBUTING.md#quality-standard) 
before sending pull request. Thanks!

Link to https://goreportcard.com/: <>

Link to https://gocover.io/: <>

Objections, comments? @avelino @shurcooL

[dmitshur]

No objections from me, that looks good.

Minor, but maybe make the first paragraph into a single sentence. Right now, it would render oddly across 3 lines:

Please check if what you want to add to awesome-go list meets quality standards before sending pull request. Thanks!

[matrixik]

Thank you for comment. When I tried it yesterday it was rendered in one line, it needed empty line between lines I wanted in separate lines (nice sentence ;) ). I will fix it if needed.

[matrixik]

I also thinking about adding as last line something like: If package have low scores inform maintainers or you could help them with PR. Or maybe you could propose some better sounding advice.

[kirillDanshin]

What do you think about adding something like this checklist and note below?

---

Note, that new categories can be added only when there are 3 packages or more.

Make shure that you've checked the boxes below before you submit PR:

• [ ] I have added my package in alphabetical order
• [ ] I know that this package was not listed before
• [ ] I have added godoc link
• [ ] I have added gocover.io link
• [ ] I have added goreportcard link
• [ ] I have read Contribution guidelines and Quality standard.

Thanks for your PR, you're awesome :+1:

---

[avelino]

+1

[kirillDanshin]

Please, review my PR (#890).