Add GitHub templates

[andygrove]

Here are suggested issue templates for bugs and features, as well as a PR template that will prompt users to enter the issue that the PR is closing.

[codecov-commenter]

Codecov Report

Merging #17 (6ee3ade) into master (74d3567) will not change coverage.
The diff coverage is n/a.

❗ Current head 6ee3ade differs from pull request most recent head e58c1ba. Consider uploading reports for the commit e58c1ba to get more accurate results

@@           Coverage Diff           @@
##           master      #17   +/-   ##
=======================================
  Coverage   82.47%   82.47%           
=======================================
  Files         162      162           
  Lines       43414    43414           
=======================================
  Hits        35805    35805           
  Misses       7609     7609           

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[alamb]

Looks like an improvement to me. I have a few suggestions, but I think it would be fine to merge as is too

[alamb]

I like to try and lead people away from a free form description of bugs as that often ends up more confusing (to me)

What would you think about the sections:

1. To Reproduce
2. Expected Behavior
3. Actual Behavior
4. Additional Context

[andygrove]

Yes, that looks good to me.

[jorgecarleitao]

Awesome, great write up and all very sensible. 👍