add travis-ci build status badge
add travis-ci build status badge


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Former-commit-id: 2f8fb74260e51907922b76f12f4a435e76ff57e4 [formerly 8fbcaaf50b97ee2c16f20ea563912649be853c5d] [formerly 1b949d233a11088406afc6620fb7a1b8faa095b2 [formerly 007b5436ebbdfb20c5e88fc3317f8609c43591d4]]
Former-commit-id: 9cdf5fdb860dc127a0bef8fe848ef395acaa2f3e [formerly 72955e9e0e42a2139ef1f37176eae0925c149c32]
Former-commit-id: 22f4049f23c522e801cee50754ae76cc848971ad
PolyJIT/benchbuild,PolyJIT/benchbuild,PolyJIT/benchbuild,PolyJIT/benchbuild