[Design Issue] Overcomplicated module children system

[Iainmon]

The system that keeps track of a module's children, their names, order, etc. is overcomplicated and should be fixed. It will impact how users interact with their models.

In lib/Network.chpl, we have,

ChAI/lib/Network.chpl

Line 271 in da80575

var subModules: moduleChildren(eltType);

which should just be a dict(string,shared Module) or something. It seems like the moduleChildren record just causes more problems and requires more overloads. Most of the iters in the module class shouldn't really be used. I wasn't able to spend too much time designing this and think it could be made much simpler.