Force-Field Organization

The different force fields should be re-organized in separate directories. A possible structure for the share/gromacs directory would be

 share/gromacs
 share/gromacs/tutor
 share/gromacs/html
 share/gromacs/force_field
 share/gromacs/force_field/gromos_XXX
 share/gromacs/force_field/encads_XXX
 share/gromacs/force_field/encadv_XXX
 share/gromacs/force_field/oplsaa_XXX
 share/gromacs/force_field/amber99_XXX
 share/gromacs/force_field/amber03_XXX
 share/gromacs/solvent
 share/gromacs/misc

where the XXX represent different versions of the force fields. Each of the force field directories can also hold topologies for solvent molecules, although it would be great to put all that in rtp files instead.

The new solvent directory would contain different equilibrated solvents for use in e.g. genbox. The directory misc would contain miscellaneous other files, like the Cool Quote database.