GitLab

* Proof of concept matching current behaviour with Breathe

* Reorganise C++ API docs to work without autosummary

* Revert to Sphinx-native search

* Move remaining pip deps to conda

* Remove unnecessary lunrsearch templates

* Remove lunrsearch from cmake

* Tidy up layout of API docs

* Get code blocks to work with Breathe

Breathe doesn't seem to support the Doxygen <preformatted> tag.
It does support the <code> tag, but better yet it supports using
<verbatim> tags to embed rst into docstrings. This commit changes
all <pre> tags to use RST verbatim, and updates the Python
documentation machinery to support it too.

* Clarified some language

* Have doxygen exclude undocumented classes and have sphinx fail on warnings for C++ API docs

* List custom forces and integrators last

* Add breathe to documentation CI

* Typo

* Fix link to custom forces in extras.rst

* Have Breathe process only public classes

* Strip OpenMM:: prefix from rst files to avoid colons in links

* Remove existing private classes from EXCLUDE_SYMBOLS

* Add comment to C++ cmake describing why we promote warnings to errors

* Revise documentation build instructions for new dependencies

Swigged python docstrings now include documented return values and type
information or their arguments. They are generated in numpydoc format.
Furthermore, all of the Python app layer docstrings have been changed
to numpydoc format. The filterPythonFiles.py script which helps to
generate the Doxygen Python API docs has been updated to reflect these
changes.

the barostats and andersen thermostat.

the System. The System inspects all of its forces and calls
usePeriodicBoundaryConditions -- it reports 'true' if at least one of its Forces
returns 'true' for usesPeriodicBoundaryConditions.

The default Force implementation is to raise an exception (NotImplementedError).
The System implementation will return true if at least one of its Forces returns
'true' for usesPeriodicBoundaryConditions, _regardless_ of whether or not one or
more of the forces does not implement the method. If at least one of the forces
does not implement usesPeriodicBoundaryConditions and all forces return false,
an OpenMMException is thrown.

Renamed methods for dealing with TabulatedFunctions to avoid problems in wrapper APIs.  Also fixed a few bugs.

Use a consistent (and more accurate) value for electric constant everywhere.  Also cleaned up handling of constants and units in various places.

Redesigned CustomNonbondedForce to eliminate combining rules and allow the expression to directly use parameters for individual particles.