Simplify ZoneInterval.ToString. This adds an extra space in the format, but we never specified the format anyway.
Simplify ZoneInterval.ToString. This adds an extra space in the format, but
we never specified the format anyway.

BenJenkinson/nodatime,nodatime/nodatime,zaccharles/nodatime,zaccharles/nodatime,zaccharles/nodatime,BenJenkinson/nodatime,malcolmr/nodatime,jskeet/nodatime,zaccharles/nodatime,jskeet/nodatime,zaccharles/nodatime,malcolmr/nodatime,malcolmr/nodatime,nodatime/nodatime,malcolmr/nodatime,zaccharles/nodatime