Update gravitational constant

[pmbremner]

Updated the gravitational constant to match the recommended value from CODATA.

The published value (with standard error in parenthesis) and the reference were added to the comments.

This change aids gravity comparisons of benchmarks with published studies.

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[bangerth]

I would love us to be able to run simulations where this is the limiting factor on the accuracy of results :-)

[bangerth]

/rebuild

[tjhei]

Well, it does matter for a few tests, apparently. 😉

[bangerth]

It turns out that a number of tests are apparently sensitive enough to actually fail now:

	241 - dynamic_core (Failed)
	278 - geoid (Failed)
	279 - geoid_no_topo (Failed)
	280 - geoid_visualization (Failed)
	302 - gravity_point_values_list (Failed)
	303 - gravity_point_values_map (Failed)
	304 - gravity_point_values_spiral (Failed)
	716 - spectral_comparison (Failed)

Would you mind updating the test outputs?

[pmbremner]

I'll start working on these

[pmbremner]

The above commits should cover all the files from the failed tests

[bangerth]

Let's see what the tester says. I only spot checked, but is your sense also that the changes are marginal and likely correct?

[pmbremner]

I believe they are correct. Some values differ by more then a marginal amount, though, such as sin and cos coefficients. But summary values were the same or nearly the same, such as CMB heat flux in dynamic_core

[bangerth]

OK, good to merge once the checks come back green!

[pmbremner]

Hmm, are the tests still failing? I must need to do something more

[tjhei]

Did you apply changes-test-results.diff as explained in the pdf manual?

[pmbremner]

The diff file has now been applied. Rene helped me apply it and to squash the commits. Hopefully this fixes it

[gassmoeller]

Looks good now.