Fix and add specs for Issue#to_reference
Fix and add specs for Issue#to_reference

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