RFR: notify: prefix event handlers with "on*"

[Robin Westberg]

On Wed, 10 Jun 2020 15:22:29 GMT, Erik Helin <ehelin at openjdk.org> wrote:

> Hi all,
> 
> please review this refactoring that prefix the event handles in the notify bot with `on` instead of `handle` (I also
> renamed some handlers for consistency).
> Testing:
> - [x] `make test` passes on Linux x64
> 
> Thanks,
> Erik

Looks nice!

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Marked as reviewed by rwestberg (Reviewer).

PR: https://git.openjdk.java.net/skara/pull/653