Lowering the runtime here to pre 7ca535aa expectations.

The longest package at the time `client/driver` shrunk significantly,
and now the longest packages take less than 5 minutes.

We do have some long running timed out projects due to a stuck shutdown,
but in completed jobs (though they failed), the longest packages took
less than 5 minutes.  The longest running packages in
https://travis-ci.org/hashicorp/nomad/jobs/464640776 were:

```
FAIL  github.com/hashicorp/nomad/nomad                                   268.089s
ok    github.com/hashicorp/nomad/drivers/docker                          203.903s  coverage:  68.8%   of  statements
ok    github.com/hashicorp/nomad/drivers/rkt                             132.104s  coverage:  65.0%   of  statements
ok    github.com/hashicorp/nomad/api                                     123.193s  coverage:  62.9%   of  statements
ok    github.com/hashicorp/nomad/command/agent                           74.657s   coverage:  72.3%   of  statements
ok    github.com/hashicorp/nomad/command                                 63.592s   coverage:  42.7%   of  statements
```