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This changes the value of LAL_GMSUN_SI in LALConstants.h to be the IAU nominal value rather than the measured value in a particular time system. This will make LAL more consistent with standard conventions of other packages such as astropy.
@patricia-schmidt @aaron.zimmerman @gregory.ashton
A few other constants were updated or introduced to the IAU nominal values. I am not sure if this counts as modifying the API though.
In lalpulsar a new constant TEMPO2_MTSUN_SI is introduced to exactly match the value of that constant in TEMPO2 for compatibility.
@karl-wette @david-keitel @matthew-pitkin
Some unit tests in lalsimulation needed to be modified by this change as the change affects the expected values.
@sebastian-khan @geraint.pratten @maria.haney