Fixed travis build

A static user can now exceed limitations for downloads. I added the travis job id as it was the simplest way and I wasn't sure if it was worth to further complicate the script for a generic solution.

Also I'm not sure why [the os was specified as mac](https://github.com/doctrine/orientdb-odm/blob/master/bin/odb-shared.sh#L70). There is a `linux` and a `multi` tag available as well, let me know if you are okay with changing it.

Lastly, is there any reason why not bump up the tested version to 1.7.10?