--limit can collide with query string on some commands

Using the new 1.5.0 there is some inconsisten behavior on some commands when trying to (naively) mix the use of the --limit command with a limit query. Some examples:

* ceilometer event-list --limit=1 # returns one item
* ceilometer event-list -q limit=1 # returns an empty list

* ceilometer resource-list --limit=1 # returns one item
* ceilometer resource-list -q limit=1 # errors as follows

  get_resources() got multiple values for keyword argument 'limit' (HTTP 500) (Request-ID: req-79132b9a-505e-4a92-bd86-b094f455ee53)

* ceilometer meter-list --limit =1 # returns one item
* ceilometer meter-list -q limit=1 # errors the same way as resource-list

* ceilometer sample-list --limit =1 # returns one item
* ceilometer sample-list -q limit=1 # errors as follows

  Unknown argument: "limit": unrecognized field in query: [<Query u'limit' eq u'1' >], valid keys: ['message_id', 'meter', 'project', 'resource', 'search_offset', 'source', 'timestamp', 'user'] (HTTP 400) (Request-ID: req-9feebef4-3e38-4ed9-91ea-09a005f1733d)

There seem to be at least two bugs here:

* the client is not constructing the right query based on its input, or at least producing an error locally before going to the server
* the server is producing a 500 when it should be producing a 400 when it gets multiple limits