improve logging

Convert all Staging logs to tag-and-data format, add some useful
logging, and clean up some ultra verbose ones.
fix determining in-use buildpack paths
fix specs for logging and buildpacks-in-use fix
Don't use --fail-fast on integration tests

We want to see *all* the failures, not just the first one.
logging improvements, simplify droplet download
Create logs directory in dea tests
Hopefully fix 5 deadlocks in Directory Server
Temporary workaround for flaky integration spec

This is not a good long-term fix, but some tests depended on files being
around for longer than 10 seconds.  It's the test that is flaky, and we
will need to fix that test (running_the_app_spec, 'actually stops the
app') when we are under less pressure to fix the build pipeline.
more logging improvements
snapshot staging tasks

We don't load them yet, but it's useful for metrics and tests.
unregister task when buildpack cache upload fails

Previously the error would be swallowed and the task would never respond
or be unregistered. This would cause it to consume resources until the
DEA was bounced.

[finishes #58671838]
Check the temp folder size it test
bump timeout for killing DEA

1 second is not enough for it to reliably stop all instances/staging
tasks.
Auto-merge remote-tracking branch 'upstream/master'