Change WikiPage.group_by_directory to use WikiPage#directory
Change WikiPage.group_by_directory to use WikiPage#directory

stoplightio/gitlabhq,iiet/iiet-git,iiet/iiet-git,mmkassem/gitlabhq,LUMC/gitlabhq,axilleas/gitlabhq,stoplightio/gitlabhq,LUMC/gitlabhq,axilleas/gitlabhq,dreampet/gitlab,iiet/iiet-git,darkrasid/gitlabhq,jirutka/gitlabhq,dreampet/gitlab,t-zuehlsdorff/gitlabhq,htve/GitlabForChinese,LUMC/gitlabhq,jirutka/gitlabhq,dplarson/gitlabhq,t-zuehlsdorff/gitlabhq,dplarson/gitlabhq,htve/GitlabForChinese,stoplightio/gitlabhq,dplarson/gitlabhq,mmkassem/gitlabhq,darkrasid/gitlabhq,t-zuehlsdorff/gitlabhq,t-zuehlsdorff/gitlabhq,dplarson/gitlabhq,dreampet/gitlab,axilleas/gitlabhq,jirutka/gitlabhq,darkrasid/gitlabhq,mmkassem/gitlabhq,darkrasid/gitlabhq,axilleas/gitlabhq,iiet/iiet-git,LUMC/gitlabhq,mmkassem/gitlabhq,dreampet/gitlab,htve/GitlabForChinese,jirutka/gitlabhq,stoplightio/gitlabhq,htve/GitlabForChinese