Remove out-of-date issues/branches

[benoistlaurent]

There are probably issues/branches that are either out-of-date either to be adapted to a more recent version of the code.

One should remove/update those.

[chantalprevost]

Thanks for the assignment.
Below is the list of stale branches,

• A = to be adapted
• O = out-to-date
• U = unknown ( == ask Adrien):

#33 Merged
O/U bugfix/addnonbon8ff2 (Updated 8 months ago by asaladin)
[CP: probably not needed any more since it has been merged; to be checked]

#41 Merged
O/U feature/merge_heligeom
[CP: probably not needed any more since it has been merged]

O/U feature/heligeom_cython (Updated 4 years ago by asaladin)
[CP: should be finished since it is now implemented in the Develop branch]

O/U feature/scorpion (Updated 2 years ago by asaladin)
[CP: should be finished since it is now implemented in the Develop branch]

A feature/modes (Updated 8 years ago by asaladin)

A feature/restraintforce (Updated 7 years ago by asaladin)

A/U liblbfgs (Updated 7 years ago by asaladin)

U tmp/pdbread (Updated 4 years ago by asaladin)

U feature/sphinx_doc (Updated 3 years ago by asaladin)

U feature/experimental/select_and_modify (Updated 3 years ago by asaladin)
[CP: I don't know what it is about]

U gh-pages (Updated 3 years ago by asaladin)

U feature/coverage (Updated 8 months ago by asaladin)