project stuff

- move some files to .github/ folder
- add an issue template
- add two more alternatives

CONTRIBUTING.md

@@ -1,11 +0,0 @@
-* Bug reports and feature requests are welcome in [the issues][issues]
-* For questions and discussion there's the [Slack room][slack]
-* Pull Requests are welcome. For more complex changes and features it's
-  recommended to open an issue first
-* About 3 or 4 pull requests accepted one gets write access to the repo.
-  Even then, possible backward incompatible changes should be discussed first
-  in an issue or pull request
-* Documentation contributions are as important as code contributions
-
-[issues]: https://github.com/go-task/task/issues
-[slack]: https://gophers.slack.com/messages/task