Possible way to have Time work without lwjgl

@msteiger & @Immortius

+    public long getRawTimeInMs() {
+        return System.currentTimeMillis();
+    }

I have no idea if this is a valid way to fix Time.   It's what I used, but I didn't actually do anything useful with the resulting headless system, and it did seem to crank the cpu.

So this is really just a discussion point rather than a PR, unless I hit the lottery and got it in one.