Dem dmt non contact

[OGaboriault]

Description

A new DMT cohesive force model has been implemented, This version uses non contact force between particles.
This force model will be useful for LPBF powder spreading simulations.

Testing

No news test have been implemented. The output of old test using the DMT model have been modified.

Documentation

A new parameter has been added. The documentation has been updated.

Miscellaneous (will be removed when merged)

Checklist (will be removed when merged)

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Code related list:

• [x] All in-code documentation related to this PR is up to date (Doxygen format)
• [x] Lethe documentation is up to date
• [x] The branch is rebased onto master
• [x] Code is indented with indent-all and .prm files (examples and tests) with prm-indent
• [x] If parameters are modified, the tests and the documentation of examples are up to date
• [ ] Changelog (CHANGELOG.md) is up to date if the refactor affects the user experience or the codebase. (I don't think Changelog is required here)

Pull request related list:

• [x] No other PR is open related to this refactoring
• [x] Labels are applied
• [x] There are at least 2 reviewers (or 1 if small feature) excluding the responsible for the merge
• [x] If this PR closes an issue or is related to a project, it is linked in the "Projects" or "Development" section
• [x] If any future works is planed, an issue is opened
• [x] The PR description is cleaned and ready for merge

[blaisb]

@OGaboriault ping me when you want a re-review