blacklist removed services from *-ctl commands

When running omnibus-ctl [status|start|restart|etc] for services
that have been removed and are configured as removed (requires
config to be written by the *-omnibus projects), we should not
attempt to start the services or run any service commands against
them unless specifically attempting to do so. Services that are
removed can still be accessed by running:

```
*-ctl SV_COMMAND REMOVED_SERVICE
```

The previous behavior manifested itself as a race condition in
Enterprise Chef where a service that was previously installed as
part of an older version came up after a `*-ctl start` and stole
the port from the service that was supposed to be running. This
fixes that issue.

/cc @opscode/server-team @stevendanna @jamesc @irvingpop @ryancragun 
@stevendanna `removed_services` differ from `disabled_services` in that the removed ones are no longer managed by the package that installed them. For instance, in the latest versions of Enterprise Chef, the `opscode-solr` service has been replaced with the `opscode-solr4` service. When running `p-c-c start`, `opscode-solr` attempts to start, and unfortunately does so successfully, taking the port away from `opscode-solr4` and really mucking things up. In this case, `opscode-solr` is not "disbaled", it's a service that was previously written by into place by the chef-solo run that we no longer want to manage when running the system-wide `*-ctl` commands.

"disabled" has a totally different meaning here. "disabled" means that chef-solo knows about the service and will still manage it, and if it wants to enable it it can create the symlink to do so. These "removed" services would actually show up as enabled without specifically calling them out.

Once *-ctl cleanup is called, the service definitions for these will get removed and this code will be a no-op.