Both Pull Request and patch are welcome

[Li Yang <li...@apache.org>]

Just want to make it clear that both Pull Requests (PR) and patch files are
welcome as the form of code contribution. And JIRA is required for both
cases to track the task.

I see the number of open PRs in github Kylin repo is growing. PR creator
please double check you also create a JIRA and attach the PR link in the
JIRA. Otherwise your PR will lose track and may not be attended.

Thanks
Yang