Make bond-atomtypes case sensitive
This change is needed for e.g. the glycam force field to work.
This change makes the bond-atomtype handling consistent with the
normal atom type handling, which was already made case sensitive.
Note that this only requires case matching internally within the
force field files, this does not affect handling of user input.
Changed the (inconsistent) bond-atomtypes to uppercase for two
dihedrals parameter lines in charmm27.
Change-Id: I27a37543393e503ab836377c992e5e0c6c57e852