GitLab

* Add draft GHA-based CI for Linux

* Fix events

* Dup key

* Fix path

* Update env vars

* More fixes

* Fix env vars again

* add doxygen

* add sudo

* Typo

* upgrade CUDA

* escape newlines

* more backslashes

* fix CUDA_APT

* more env vars fixes

* fix missing file

* acumulate env_vars

* build python wrappers only if requested

* add pytest

* use $GITHUB_ENV

https://docs.github.com/en/free-pro-team@latest/actions/reference/workflow-commands-for-github-actions#environment-files

* use ${GITHUB_WORKSPACE}

* Pin older gromacs

* add windows

* Provide default values for unbound vars

* fixes

* this is powershell not cmd

* update envs

* win fix

* make windows use cmd

* Change install prefix

* fixes

* better env files

* Increase timeout threshold

* set xcode to 10.x

* specify action version

* fix sdk in macos

* split jobs a bit more

* build wrappers even if tests failed for c...

Updated examples and snapshot of wrappers to what I think is their final form. Fortran no longer uses a RuntimeObjects structure; instead it passes around an opaque handle directly to the Context.

- updated the Readme file

I'm checking in very early attempts at OpenMM Hello World examples so Chris and I can work on them together.