Merge pull request #5 from mlund/master

Latest version
Delete unsued variable in Faunus::Potential::HydrophobicWall<T>::_info()
Updated peptide.cpp to include free energy contour plots by residue.
Another change in peptide.cpp
Reintroduced MassCenterConstrain as well as Fernando playground.
Added extra assertions to MassCenterConstrain energy term.
Merge pull request #6 from mlund/master

Get latest changes to main branch.
Merge pull request #27 from jmhenriques/master

Minor but important change.
Merge pull request #1 from mlund/master

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