postcohtable: Remove detector names from table

Breaking change.

This change removes detector names from the various data structures that are used throughout the pipeline and ensures that all pointers into the data structures have their offsets based upon the number of interferometers.

Previously, adding support for an additional interferometer to the pipeline would involve modifying all of the below files, and would often require extensive testing to ensure that the massive number of changes that would need to be done would be correct.

With these changes, when adding interferometers, the only file that needs to be changed is gstlal-spiir/include/pipe_macro.h, with the modification of MAX_NIFO, IFOMap and IFOComboMap. By changing these variables, the next compilation of the pipeline will automatically support the new interferometer.

For this to be automatically tested, we will require some rework of the unit test comparisons, as the names of columns will change, as will the order of some of them.