Update default ARKODE methods

[Steven-Roberts]

Replaces #345

In draft status until we settle on the defaults. Then I'll update the docs and output files.

Justification:

• ARK order >2: Follows the recommendations in the conclusion of https://doi.org/10.1016/j.apnum.2018.10.007
• ERK order 4: Improved principal error and embedded quality metrics
• ERK order 5: Improved principal error and embedded quality metrics
• ERK order 8: Switch to a method designed for local extrapolation mode. Likely better principal error but need to confirm
• IRK order 2: Improved principal error, L-stability, and stage order 2
• IRK order >2: Follows the recommendations in the conclusion of https://doi.org/10.1016/j.apnum.2019.07.008

[Steven-Roberts]

@gardner48 @drreynolds can you confirm this is the table format you're looking for:
https://sundials--547.org.readthedocs.build/en/547/arkode/Butcher_link.html#id61

If that looks good, I'll do the same for DIRK and SPRK (MRI already exists). I'll also remove all the corresponding constants from Constants.rst.

[gardner48]

@gardner48 @drreynolds can you confirm this is the table format you're looking for: https://sundials--547.org.readthedocs.build/en/547/arkode/Butcher_link.html#id61

If that looks good, I'll do the same for DIRK and SPRK (MRI already exists). I'll also remove all the corresponding constants from Constants.rst.

Yes, that's what I was thinking