Release 1.33

- Make mp_rat_read_cstring more consistent with mp_int_read_cstring.
- Include the standard ubuntu-24.04-arm runner type in the CI matrix.
- Update some of the Python test support code.

Release 1.32.

Add const qualifiers to global static data. (#53)

There are no other API or functionality changes in this release.  Includes
documentation and formatting cleanup, and some fixes to the tests and test
scripts.

Related commits:

 - 048b49c Reorganize allocation to make cleanup simpler.
 - 18404fb Add a unit test for 4096 decimal digits of pi.
 - e6d37f2 Merge pull request #42 from creachadair/pi-dynamic-output-buffer
 - 9d6dfa1 Update test scripts to use Python 3.

Tag release 1.31.

There are no functional changes in this release. Other than some documentation
cleanup, the main changes are the addition of a Travis CI configuration, and
some fixes to the Makefile.

Tag release 1.31.

There are no functional changes in this release. Other than some documentation
cleanup, the main changes are the addition of a Travis CI configuration, and
some fixes to the Makefile.

Tag release 1.30.

Improve test automation; no functional changes to the library.

Tag release 1.29.

Documentation Edition. The main improvement here is that the API documentation
is now unified in the header files, and doc.md is now generated from a template
that includes the text from the headers. The automation for this is still
unsatisfactory, but it is better than it was.

Tag release 1.28.

Tag release 1.27.

Tag release 1.26.

Tag release 1.25.