Fix Travis failures.

Fixes two issues with Travis:

* Travis has inadvertently reverted to Git 1.7.9.5. This has been
  reported, and the suggested work around was to update git prior to
  running our script.  See
  [here](https://github.com/travis-ci/travis-ci   /issues/1710) for details.

* The prior `script` was apparently invalid YAML (the `\[` is interpreted
  as an escape sequence).