add min/max to Rational
add min/max to Rational

kevinmeredith/spire,rklaehn/spire,codeaudit/spire,kevinmeredith/spire,AlecZorab/spire,guersam/spire,siddhartha-gadgil/spire,siddhartha-gadgil/spire,non/spire,guersam/spire,adampingel/spire,tixxit/spire,woparry/spire,adampingel/spire,rklaehn/spire,JackSullivan/spire,woparry/spire,tixxit/spire,codeaudit/spire,AlecZorab/spire,JackSullivan/spire,non/spire