Modules: Additional improvements to CLI completion.

Replace 'needsreload' argument with a 'type' argument to specify which
type of modules you want completion.  This provides more accurate CLI
completion for load and unload commands.

* 'module unload' now excludes modules that have active references or are
  not running.
* 'module load' now excludes modules that are already running.
* 'core set debug [atleast] <level> [module]' shows running modules only.

ASTERISK-27378

Change-Id: Iea3e00054461484196c46f688f02635cc886bad1