snglinspiraltable.c: remove richcompare()
this method was used to implement GPS time comparisons for the coincidence code, but the coincidence code now performs the time comparisons internally and so this additional complexity is not required. after this is merged, you must be using the head of lalsuite's master branch (or any branch with 7eef7079ec7a112132bd11eb292c5535d2ebf6b2 included).