refs https://github.com/TryGhost/Ghost/issues/9623
- add `oembed-parser` module for checking provider availability for a url and fetching data from the provider
- require it in the `overrides.js` file before the general Promise override so that the `promise-wrt` sub-dependency doesn't attempt to extend the Bluebird promise implementation
- add `/oembed` authenticated endpoint
- takes `?url=` query parameter to match against known providers
- adds safeguard against oembed-parser's providers list not recognising http+https and www+non-www
- responds with `ValidationError` if no provider is found
- responds with oembed response from matched provider's oembed endpoint if match is found
refs #7189
- we had a memory leak after upgrading to knex 0.11.x
- knex has published a new version 0.12.x
- the memory leak does not longer exists
- knex has reverted their pool logic, see https://github.com/tgriesser/knex/pull/1665
issues #6406#6399
- all dates are stored as UTC with this commit
- use moment.tz.setDefault('UTC')
- add migration file to recalculate local datetimes to UTC
- store all dates in same format into our three supported databases
- add option to remeber migrations inside settings (core)
- support DST offset for migration
- ensure we force UTC in test env
- run whole migration as transaction
- extend: Settings.findOne function
