lib, doc: add "route-map NAME optimization" command

lib, doc: add "route-map NAME optimization" command

Currently we have a "route-map optimization" command which is entered
from inside the route-map entry but actually applies to the whole
route-map. In addition, this command is not shown in the running-config
and not stored to the startup-config during "write".

Let's add a new command on the config node level to control this setting
and show it in the running-config to make possible to save it during
"write".

The old command is saved for the backward compatibility but hidden and
marked as deprecated.

Signed-off-by: Igor Ryzhov <iryzhov@nfware.com>