The chef-server attributes includes `despsolver_timeout` but that
value wasn't applied anywhere. Changed that value to match the
hard-coded value, 2000, at

    https://github.com/opscode/chef_objects/blob/master/src/chef_depsolver.erl#L46

and updated erchef.config to use that value per

   https://github.com/opscode/chef_objects/blob/master/src/chef_depsolver.erl#L127
The desired default for the depsolver timeout is 5000

This matches what is in enterprise chef and this will keep open source
consistent with enterprise chef in this area
Merge branch 'mm/depsolver_timeout'