v2.0 double-precision logistic regression bugfix posted

[Christopher Chang]

The 21 Nov 2023 plink2 builds fix a serious issue with the double-precision logistic regression in Jan-Oct 2023 builds.  (The issue did not affect older plink2 builds, the single-precision mode, or the Firth regression mode.)  We recommend rerunning affected logistic regressions.

Major enhancements since the Mar 2017 build include:

- Linear regression that is often hundreds or even thousands of times as fast as PLINK 1.9, with no loss of accuracy.

- VCF dosage import/export.

- Most commonly-used PLINK 1.9 commands, with the remaining major exception of non-concatenating merge.  (plink2's take on --r2 isn't done yet, but it should be completed within the next week.)  Many rough edges in the PLINK 1.x form of these commands have been addressed.

- Several additional sanity checks (which can be overridden).

[Christopher Chang]

Correction, the Firth regression mode was potentially affected by the bug.