v/.github/PULL_REQUEST_TEMPLATE

Please title your PR as follows: `time: fix foo bar`. Always start with the thing you are fixing, then describe the fix.
Don't use past tense (e.g. "fixed foo bar").

Explain what your PR does and why.

Before submitting a PR, please run the tests with `make test`, and make sure V can still compile itself. Run this twice:

./v -o v
./v -o v

I try to process PRs as soon as possible. They should be handled within 24 hours.

Applying labels to PRs is not needed.

Thanks a lot for your contribution!