fix issue with 'display:flex', closes #77
fix issue with 'display:flex', closes #77

rlowry/jquery-match-height,2947721120/jquery-match-height,rlowry/jquery-match-height,2947721120/jquery-match-height,liabru/jquery-match-height,liabru/jquery-match-height,slackero/jquery-match-height