Implement database listeners and make database notify on jobs change

[ylei-tsubame]

This PR contains the foundation work for #801.

Changes:

• The database will notify when the jobs table gets an insert or update change.
• The database perl module will have the basic methods for managing the database listeners which can receive and react to the notify calls from the database.
• anvil-daemon will react to notify calls triggered by the jobs table.
• anvil-access-module will use Proc::Simple as a replacement for fork() to keep the code base cleaner.

Additional thoughts:
The functions provided in anvil-access-module to manage database listeners may not be needed since the listener-related logic was moved to the database perl module. But it's kept in place for convenience.

If more control is required, try using the methods directly with JSON as parameters, like: x Database->add_listener '{"param1":"value1",...}'

Got confused, ^ is actually required. Can't write perl subroutines in javascript.

Update 1:
Some changes broke the communication between the striker-ui-api and its child anvil-access-module. Added a transitional patch which will be changed in the next PR.

Update 2:
Removed patch from update 1 because it's not actually solving the problem. The communication between striker-ui-api and its child anvil-access-module will still break (or mismatch) sometimes. Logs show DBI::dbh->clone() is stuck and causes the response to never be sent.

Update 3:
Made a log enhancement for update 2, which shouldn't have fixed the problem in update 2, but I'm having trouble reproducing the problem now... 😭

Update 4:
The problem from update 2 persists; although not always reproducible. It may be caused by the listeners' high-res sleep?

[ylei-tsubame]

retest this please

[digimer]

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[digimer]

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[digimer]

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