Release 6.4.4 (MODFLOW-USGS#1616)

* fix(par): first version of message cache for MPI traffic (MODFLOW-USGS#1582)

* - cache mpi headers and bodies
* - final step in implementing caching: only cache message bodies (skip routing of headers and maps when possible)
* - fix: initialize mpi request handles
* - add MPI error check
* - PETSc vec readonly access
* - add more strategic MPI error checks

* fix(mvr): improve water mover performance (MODFLOW-USGS#1605)

* docs(mf6io): correct description of CDIST in gwfgwf/gwtgwt (MODFLOW-USGS#1606)

* docs(mf6io): correct description of CDIST in gwfgwf/gwtgwt
* correct deprecation warnings to use proper version number

* Prepare 6.4.4 release

* test: use v14 of executables distribution (MODFLOW-USGS#1614)

* v15 of exes distribution doesn't have double-precision program versions
* temporary workaround until double-prec mf2005/mfnwt/etc restored to dist

* ci(release): update version to 6.4.4

---------

Co-authored-by: mjr-deltares <[email protected]>
Co-authored-by: langevin-usgs <[email protected]>
Co-authored-by: wpbonelli <[email protected]>
Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>

Merge pull request MODFLOW-USGS#1594 from MODFLOW-USGS/v6.4.3

Release 6.4.3

feat(ArrayHandlers): add 2D array expansion interface (MODFLOW-USGS#1382

)

feat(ArrayHandlers): add 2D array expansion interface (MODFLOW-USGS#1382

)

feat(idm): update EVT package for IDM (MODFLOW-USGS#1385)

* update EVT package for IDM

* rebuild makefiles

* cleanup including dis, evt, and post-rebase

---------

Co-authored-by: mjreno <[email protected]>

fix(par): backtracking was out of sync (MODFLOW-USGS#1343)

docs: update deprecated config in .readthedocs.yml (MODFLOW-USGS#1336)

docs: update deprecated config in .readthedocs.yml (MODFLOW-USGS#1336)

docs: update deprecated config in .readthedocs.yml (MODFLOW-USGS#1336)

fix(lak,sfr,uzf): fix nullptr when deallocating package in validate m…

…ode (MODFLOW-USGS#1331)

Co-authored-by: mjreno <[email protected]>