Mega grabbag PR

[orta]

It started off pretty normal, but turned into a bit of a mega PR

• I think it fixes Fix for platformResultsPreMapper/concat problem #355 - I now have a check on every issue which uses those APIs org/checkTemplate.ts so I should be able to test that
• I've been trying to fix Triggering scheduled future tasks is unreliable #347 all day yesterday, not really sold that I got it though
• Removed Apollo engine, I wasn't using it and occasionally it would fill my logs (and v2 API migration changes were non-obvious)
• Fixes If the peril settings json is malformed, peril crashes #349
• Adds support for a slack URL which can send messages about positives or failures
• Adds support for not prefixing all of your peril.settings.json in the same route as your settings repo
• Adds support for sending all peril logs into slack if you've set up the installation in staging

[orta]

merge on green