Adjust the text of about to match our website
Adjust the text of about to match our website

Also tweaked the initial size of the dialog a litle to offer more
space for the version information.

mathturtle/tomviz,cjh1/tomviz,mathturtle/tomviz,OpenChemistry/tomviz,cryos/tomviz,thewtex/tomviz,cjh1/tomviz,cryos/tomviz,cryos/tomviz,OpenChemistry/tomviz,OpenChemistry/tomviz,cjh1/tomviz,mathturtle/tomviz,thewtex/tomviz,OpenChemistry/tomviz,thewtex/tomviz