Add templates for feature-request, bug-report, docs-improvement

[dinjazelena]

When creating Issue, template will be provided to users to have standardized way of tackling issues and discussion.
closes #164

[dinjazelena]

@MrPowers, hey so this is kinda hard to test, cos it requires merge to main in order to take full effect. I can show u with screenshots how it looks like? But in general for bug-reports:

1. reproduce minimal example of bug
2. issue description
3. expected behavior

Check if u are using latest quinn version.
Adds bug label to issue. and BUG: suffix in order to filter out all issues.

Open a ISSUE here on repository to see how it looks:
https://github.com/dinjazelena/test-issues

[dinjazelena]

@MrPowers , @SemyonSinchenko , so its very generic templates for issues, so i think we ca just merge it and check it out and just have fixes if there is something that u want to change. Otherwise i also added it to test repo so u can check how it looks:
https://github.com/dinjazelena/test-issues Go Issue, New Issue, and have a look.

[SemyonSinchenko]

May you add something like Question?

[dinjazelena]

@SemyonSinchenko , so its totally up to us and our imagination really. Maybe for questions we could have discussion panel
https://docs.github.com/en/discussions/quickstart.
But i could see it being just irrelevant cos its not like its so huge community, and kinda more verbose and transparent if its in Issue.
So up to u to decide really.

[SemyonSinchenko]

@MrPowers what do you think about this?

[SemyonSinchenko]

@dinjazelena May you also update CONTRIBUTING.md file? Tnx

[SemyonSinchenko]

@dinjazelena Is there any progress here? Do you need help? In the case if you wont have time for it anymore, please notify us here about it. It is absolutely OK, we just reassign this ticket in such a case!

[dinjazelena]

Templates for Issues and PR is done.

[SemyonSinchenko]

LGTM

[MrPowers]

LGTM