Disables toggle if negative heights present.
Disables toggle if negative heights present.

The toggling of scale between theoretical and observed height has been
disabled when negative heights are present, because the negative heights
have no theoretical maximum and so only the positive scale could be
modified. This just looks wrong, so I turned it off.

ProteinsWebTeam/LogoServer,ProteinsWebTeam/LogoServer,Janelia-Farm-Xfam/LogoServer,Janelia-Farm-Xfam/LogoServer,ProteinsWebTeam/LogoServer,ProteinsWebTeam/LogoServer,Janelia-Farm-Xfam/LogoServer,Janelia-Farm-Xfam/LogoServer,ProteinsWebTeam/LogoServer,Janelia-Farm-Xfam/LogoServer,ProteinsWebTeam/LogoServer,Janelia-Farm-Xfam/LogoServer