This feature is a request to add a single feature flag named featureFlagAll to mongd that will have the effect of setting all existing feature flags to true, regardless of other flag settings.

Motivation: Evergreen and resmoke.py often do "all feature flags" runs, but there is no way to specify all feature flags when manually starting a mongod from the command line. This makes it impossible for development to reproduce the same flag settings as BFs and patch build failures they are investigating in cases where a local reproduction requires a mongod to be started manually. This includes Genny benchmarks (genny repo) and microbenchmarks (mongo-perf repo).

Note that if this feature existed, then resmoke.py itself could also be simplified to use it instead of having to find and individually enable all the individual feature flags.