FLUID-4392 additive demands blocks

[Antranig Basman]

http://issues.fluidproject.org/browse/FLUID-4392

Perhaps not entirely unexpectedly, surveying the codebase shows this not to be the light couple of hours' 
work I was thinking... one of the main complicating factors is the awful fluid.alias system which is 
targetted for removal from the framework as soon as possible. This is showing itself to be just as much of a 
hazard in implementation as it is in use, and is obstructing the main code path which would be used for 
operating additive demands resolution. It should be possible to take the system in a number of good 
directions at once, with
i) implementing a basic but effective "wrappers" system
ii) destroying fluid.alias
iii) enabling additivity in demands blocks
iv) allowing for multiple type names per components, preparing the way for the globally ginger world

without doing anything too fundamental or expensive, but unfortunately during this week a higher priority is 
getting UIOptions ready for freeze and addressing colinclark's painful integration points found over the 
weekend with UIOptions in Wordpress. So I'll unfortunately have to push this work out to the weekend - if 
you can hang in there for a bit, Charly, I should be able to have something sort of usable by Monday.
Unfortunately I don't think I can suggest any particularly sensible workaround for your case with the 
captions editor - the only real way out at the moment is to copy out the contents of your demands block 
which match the controller into a duplicated one which matches the "non-controller" case with the 
controller-specific parts missing. This is what yzenevich has to do in CollectionSpace a lot at the moment.
Sorry - until soon,
Antranig