libevoral itself doesn't seem to need libpthread - but by some mechanism it #includes <pbd/event_loop.h> (which now does #include <pthread.h>). So let's make sure it can be found.
Among other things, this means that automation controls/lists have the actual
min/max/normal/toggled of parameters, and not those inferred from the Parameter
ID, which is not correct for things like plugin parameters.
Pushing things down to the Evoral::ParmeterDescriptor may be useful in the
future to have lists do smarter things based on parameter range, but currently
I have just pushed down the above-mentioned currently used attributes.
This is not used anywhere in Evoral and is just a wrapper around the PBD
RingBuffer anyway. Towards a (once again?) independently buildable/testable
Evoral and fewer cross-dependencies.
It'd be nice if we could use 'ARDOUR::config_dir_name' for this purpose (or perhaps 'PROGRAM_VERSION'). However, neither is implemented widely enough at present to make this practical. Keep an eye on them though, as possible future strategies.
