Bump src/hm9000

Bump cloudfoundry/hm-workspace:
  Onsi Fakhouri:
     bump test suite.  now with better english ( Travis created: https://travis-ci.org/cloudfoundry/hm-workspace/builds/15373159 )
     add keep-alive to start messages sent by evacuator ( Travis started: https://travis-ci.org/cloudfoundry/hm-workspace/builds/15373054 )
  Onsi Fakhouri and Phan Le:
     tweak worker pool index computation ( Travis Success: https://travis-ci.org/cloudfoundry/hm-workspace/builds/15244642 )