UNBLOCK command

The current behaviour of the block button with channels specified goes back to the beginning of Eos, before that Obsession and so probably all the way back to Light Palette.

Chan BLOCK enter will actually UNBLOCK a channel if it was blocked. It will BLOCK a channel if the channel was unblocked.

This was probably sensible behaviour when channels only had one parameter, intensity.

It's more problematic. when channels have multiple attributes, since chan BLOCK will unblock any of the attributes of the channel that are blocked. chan BLOCK will then block all of the attributes of the channel.

The problems with this are:

- behaviour unpredictable - particularly for complex channels where not all of the parameters are visible on-screen

- behaviour can't be made into a macro because the end state depends on the start state which the macro can't know.

It's be great to have definite BLOCK and UNBLOCK functions, even if only available as commands in macros.

Writing the makes me wonder all over again that this hasn't already been implemented, so maybe it has and I just don't know the secret commands?

If not, it'd be a great new pair of functions.

Ta,

Rob.