Namespaces, revisited.

I conservatively extended namespaces, but that took an internal overhaul of how scopes are treated. Shorthands are syntactic sugar for full-blown expressions.

using System

The above is sugar for:

using System (c0, c1, c2, ...)

Where c0, c1, c2, ... are all combinators in the System workspace. And that is sugar for:

using ε = System (c0, c1, c2, ...)

Which is again sugar for a number of renames.

using ε = System (c0 = c0, c1 = c1, c2 = c2, ...)

The renames all introduce bound names into the current scope. E.g.,

using Sys = System (p = print)

This will bind 'Sys::p' to 'System::print'.