[Bro-Dev] script loading changes

[Gilbert Clark]

Apologies if I'm missing the point / this already exists :)  That being 
said...

>> 3) A new "@add x when y ..." directive that's an alternative to @load, and
>>     can be used to conditionally load script named 'x' only when the script
>>     named 'y' has already been loaded.  The evaluation of that condition is
>>     postponed until after all scripts specified via @load or as command line
>>     arguments have been loaded.  'x' and 'y' can be named according to either
>>     (1) or (2) above.
>

Rather than an "@add x when y", what about "@allows x" defined within y, 
where @allows was evaluated with the stipulations described above?

Alternatively, @try x, then define a set of @require directives in x 
that must be met in order for x to be loaded (but that silently fail / 
throw a warning if they fail to load)?

--Gilbert