Switch CI to travis-ci, fix build badge.
Switch CI to travis-ci, fix build badge.

jevonearth/rtpproxy,synety-jdebp/rtpproxy,Vocalocity/rtpproxy-pre,jevonearth/rtpproxy,hongbinz/rtpproxy,synety-jdebp/rtpproxy,hongbinz/rtpproxy,Vocalocity/rtpproxy-pre,Vocalocity/rtpproxy-pre,dsanders11/rtpproxy,jevonearth/rtpproxy,sippy/rtpproxy,dsanders11/rtpproxy,sippy/rtpproxy,hongbinz/rtpproxy,jevonearth/rtpproxy,synety-jdebp/rtpproxy,dsanders11/rtpproxy,Vocalocity/rtpproxy-pre,sippy/rtpproxy,synety-jdebp/rtpproxy,hongbinz/rtpproxy