Make wave region option queries time based

[mgalloy]

Some of the options per wave region change by time, so allow querying by lime like the epoch query function of ucomp_run, i.e.:

flat_values_range = run->line('1074', 'flat_values_range', datetime='2022-01-21')

[mgalloy]

I can make each wave region its own file, i.e., ucomp.1074.spec.cfg and ucomp.1074.cfg. Then use the wave_region argument of line to find the correct file, then use the option name and date/time like a normal epoch file.

• [x] split current lines file and lines spec file into a pair of files for each wave region
• [x] verify each pair of config files in ucomp_run::init
• [x] write a new ucomp_run::line method that has a datetime argument similar to the epoch method
• [x] make sure datetime is set for each line method call in the code