Inline Cache is broken for the repl

[jonnyboyC]

Running the following in the repl blows up

class A {
  init() {
    @a = 10;
  }
}
let b = A();

This occurs because repl shares a single module. Currently compile each line one at a time which in term nukes the inline cache. When we then attempt a lookup for @a = 10 we miss the cache and bail out.

There are many options here for how to address.

• We could have each line block of code entered be a module with all previous modules exporting all symbols forward.
• We could compile all the statements that have been put into repl as one increasing long script. We'd then need a mechanism to jump to the instruction indicating the start of the current line.
• Probably several more but I'll need time to thing about it.