Merge branch 'v2.5'

conda/plumed/meta.yaml

src/multicolvar/InPlaneDistances.cpp

user-doc/spelling_words.dict

user-doc/tutorials/aa-lugano-5.txt

user-doc/tutorials/aa-lugano-6a.txt

user-doc/tutorials/lugano-5/.solutions/plumed_ex1.dat

user-doc/tutorials/lugano-5/.solutions/plumed_ex2.dat

user-doc/tutorials/lugano-5/.solutions/plumed_ex3.dat

user-doc/tutorials/lugano-5/.solutions/plumed_ex4.dat

user-doc/tutorials/lugano-5/.solutions/plumed_ex5.dat

user-doc/tutorials/lugano-5/beta-hairpin.pdb

user-doc/tutorials/lugano-6a/.solutions/plumed_ex1.dat

user-doc/tutorials/lugano-6a/.solutions/plumed_ex3.dat

user-doc/tutorials/lugano-6a/lammps-equilibration.in

user-doc/tutorials/lugano-6a/lammps-production.in

user-doc/tutorials/lugano-6a/xdistances.dat