Remove travis build badge
Remove travis build badge

Signed-off-by: Johannes 'fish' Ziemke <64b2b6d12bfe4baae7dad3d018f8cbf6b0e7a044@freigeist.org>

derekmarcotte/node_exporter,derekmarcotte/node_exporter,siavashs/node_exporter,siavashs/node_exporter,siavashs/node_exporter,siavashs/node_exporter,prometheus/node_exporter,prometheus/node_exporter,derekmarcotte/node_exporter,prometheus/node_exporter,derekmarcotte/node_exporter