Improve wording on disabling impersonation in api/README
Improve wording on disabling impersonation in api/README

iiet/iiet-git,dreampet/gitlab,stoplightio/gitlabhq,axilleas/gitlabhq,iiet/iiet-git,axilleas/gitlabhq,iiet/iiet-git,axilleas/gitlabhq,mmkassem/gitlabhq,mmkassem/gitlabhq,dreampet/gitlab,mmkassem/gitlabhq,dreampet/gitlab,iiet/iiet-git,axilleas/gitlabhq,stoplightio/gitlabhq,stoplightio/gitlabhq,dreampet/gitlab,mmkassem/gitlabhq,stoplightio/gitlabhq