Classes with `$` in their name may produce illegal output code

Due to, I believe, the usage of $ to denote inner classes, if a class is decompiled which references a class like that, without that other class being on the decompilation classpath, the output code unconditionally splits, resulting in illegal code.

I've provided some example files (apologies for the package, it was simply the dev env I had open at the time, and I wanted to submit this before sleep), comments added by me:

A.class:

import mc.itemflexer.A..B; // Illegal import

public class A {
    B b = new B(this);

    public A() {
    }
}

C.class:

import mc.itemflexer.C..2; // Illegal import + class name

public class C {
    2 b = new 2(this); // Illegal class name

    public C() {
    }
}

E.class (Same as C, but not compiled as an inner class):

import mc.itemflexer..1; // Illegal import + class name

public class E {
    1 one = new 1(); // Illegal class name

    public E() {
    }
}

Vineflower / vineflower

Classes with `$` in their name may produce illegal output code #171