Context config now supports run range

[FaroutYLq]

The maximum_run_number and minimum_run_number will also be compared to the ones in reprocessing.ini, and we will take the intersection of the two ranges.

Fixed #105 and #100.

Example use:

reprox-find-data --context xenonnt_online --context-kwargs '{"minimum_run_number":51379,"maximum_run_number":52358}' --targets cut_daq_veto

[coveralls]

coverage: 68.463% (-1.3%) from 69.796% when pulling e2ba7d4 on config-kwargs into f70530b on master.