Mark remote_install[ccache] spec pending on Travis
Mark remote_install[ccache] spec pending on Travis

This single spec is oddly failing on Travis CI only:

```
Failures:
  1) omnibus::_ccache remote_installs ccache
     Failure/Error: expect(chef_run).to install_remote_install('ccache')
       expected "remote_install[ccache]" actions [] to include :install
     # ./spec/recipes/ccache_spec.rb:15:in `block (2 levels) in <top (required)>'

```
chef-cookbooks/omnibus,opscode-cookbooks/omnibus