replaces testgrouper with grouper examples
replaces testgrouper with grouper examples

jkhoogland/cppitertools,jkhoogland/cppitertools,tempbottle/cppitertools,ryanhaining/cppitertools,jkhoogland/cppitertools,tempbottle/cppitertools,ryanhaining/cppitertools,tempbottle/cppitertools,ryanhaining/cppitertools