Change default login regex to allow dots.
Change default login regex to allow dots.

This was a request by @bcd123

kotfic/girder,girder/girder,RafaelPalomar/girder,RafaelPalomar/girder,Xarthisius/girder,salamb/girder,Xarthisius/girder,adsorensen/girder,data-exp-lab/girder,kotfic/girder,sutartmelson/girder,kotfic/girder,girder/girder,sutartmelson/girder,manthey/girder,sutartmelson/girder,sutartmelson/girder,adsorensen/girder,manthey/girder,salamb/girder,Kitware/girder,manthey/girder,girder/girder,kotfic/girder,sutartmelson/girder,Xarthisius/girder,salamb/girder,adsorensen/girder,jbeezley/girder,data-exp-lab/girder,jbeezley/girder,Kitware/girder,kotfic/girder,Xarthisius/girder,jbeezley/girder,salamb/girder,jbeezley/girder,data-exp-lab/girder,adsorensen/girder,RafaelPalomar/girder,manthey/girder,Xarthisius/girder,RafaelPalomar/girder,Kitware/girder,data-exp-lab/girder,RafaelPalomar/girder,salamb/girder,data-exp-lab/girder,girder/girder,Kitware/girder,adsorensen/girder