Add continuous integration with GitHub actions

[Gjacquenot]

This pull request adds continuous integration with GitHub actions

It includes:

• tiny refactoring of Makefile to avoid duplication
• new Makefile targets to compile Nemoh programs with docker and a gcc base image
• a fix in input data that created a crash while running cylinder demo (one read a float and an integer was expected)
• continuous integration with GitHub actions

Result of continuous integration can be seen here:
https://github.com/Gjacquenot/Nemoh/runs/1760071482

I am ok to discuss any point!

[gducrozet]

This project has migrated to GitLab: https://gitlab.com/lheea/Nemoh

CI/CD has been included there, feel free to test the new Release!