Revert deprecation of frameCPP API
This PR undoes #370 and a small number of related commits by reinstating frameCPP as the primary GWF API for TimeSeries.read/write
and friends.
frameCPP
is significantly faster than lalframe
when the channel type (adc
, proc
, or sim
) is known and the frame file name can be trusted to present the frame epochs (which isn't true in general).
This PR also improves the unit tests for GWF I/O, and documentation.