[profiler] Move argument parsing to arg-parsing.c and significantly rework argument...

[profiler] Move argument parsing to arg-parsing.c and significantly rework argument parsing.

This removes all [no]foo weirdness and flag dancing in favor a simpler model.

Users can enable/disable both events and profiling modes. We expose pretty much all individual events.

A profiling feature is a group of flags that enable a specific profiling scenario.
	Right now we have code coverage, perf sampling, gc alloc and heap dump as features.

All events can be prefixed with 'no' and cause them to be disabled. We'll later introduce some sanity
checking around misconfiguration.

Finally, this changes the default set of enabled events to threads and gc. Everything else must be added on top.
Experience has shown that the vast majority of those events are just noise when profiling and the current configuration
design made it quite awkward to introduce quieter modes.