Add extended window.onerror support (#48).

Chrome Canary now supports sending a column number & stacktrace to window.onerror.

This patch enables TraceKit's window.onerror handler to use that stack trace if it exists. Additionally, it adds checks preventing the default setTimeout/setInterval wrapper from executing if this extended onerror arity is present.

Since this wrapping has been extended out to a plugin, I resurrected the old jQuery event/ajax wrappers as a plugin. Along with the async plugin, it now exists in /plugins.

The build was broken previously - this patch fixes it by disabling ADVANCED_OPTIMZATIONS. Building the project will result in a tracekit.min.js and tracekit.noplugins.min.js.

See the commit comments for more.