Domain stack fixes

[cxreg]

Make domains a little safer by avoiding potentially unbounded stack bloat

The following code will cause the stack to grow:

var d = require("domain");

setTimeout(function() {
    console.log('domain stack length is now ' + d._stack.length);
}, 100);

d.create().run(function() {
    d.create().run(function() {
        d.create().run(function() {
            d.create().on("error", function(e) {
                console.log("caught " + e)
            }).run(function() {
                    throw new Error("died")
            })
        })
    })
})

[isaacs]

Please rebase onto master and add a test. (Note that the uncaughtException stuff has been moved to src/node.js)

[cxreg]

I can't change the base branch on this PR so I'll close and re-submit

[cxreg]

Re-filed as PR #4621