Add European mode

For Aloodo, European mode works the same as regular
mode.

This is to help test browser extensions that look
for sites that treat European and non-European users
differently.

Extensions can test if the page they're on has Aloodo
and European mode is available, with:

```
window.aloodo && typeof(aloodo.setEuropeanMode)
```

Example (work in progress):
  https://github.com/dmarti/trans-europa-express

track.js

@@ -68,19 +68,29 @@
		console.log('[Aloodo]['+method+'] '+message);
	};
	
	Aloodo.prototype.setOption = function(options, value) {
		if(value !== undefined) {
			var key = options;
			options = {};
			options[key] = value;
		}
		for(var option in options) {
			this._options[option] = options[option];
			this._dlog('setOption', 'The option "'+option+'" was assigned to "'+options[option]+'"');
	Aloodo.prototype.getOption = function(key) {
		if (this._options.hasOwnProperty(key)) { 
			return this._options[key];
		} else {
			return undefined;
		}
	};

	Aloodo.prototype.setOption = function(key, value) {
		this._options[key] = value;
		this._dlog('setOption', 'The option "' + key + '" was assigned the value "'+this._options[key]+'"');
		return this;
	};

	Aloodo.prototype.setEuropeanMode = function(value) {
		this._dlog('Setting European Mode to: ' + value);
		return this.setOption('EuropeanMode', value);
	};

	Aloodo.prototype.getEuropeanMode = function(value) {
		return this.getOption('EuropeanMode');
	};

	Aloodo.prototype._addIFrame = function() {
		function postMsg() {
			window.postMessage('Aloodo iframe loaded', '*');