0.8.6-bugfix branch.

Adds one instance in NEWS

I thought the comments where pretty clear.

before they become an endangered species

(disk full?)

This commit should show the correct dialogs in the correct order. It keeps the previous behaviour of the "Streaming" from the "Media" menu. 
/!\ The intelligence is surely not accurate and stream() may need to be redirected to playOrEnqueue as open() and enqueue() do in order to be correctly parsed before... Need a bit more knowledge on playlist to be sure.

* Core: add var_Command function. This is used to execute a command registered on a object with a given name.
* rc.c: use var_Command (instead of own code)
* telnet.c: add support for object commands (like in the rc interface)