Add travis build status to README.md
Add travis build status to README.md

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