Add Settings api, and xpathCompression setting for Android

Same as last, time, you need to use my fork of wd.js to run the tests...
No, I'm with @bootstraponline's first impulse.  I not convinced the additonal complexity is justified.  What about something like this:

```
this.settings._ignoreViews = fase;
Object.defineProperty( this.settings, "ignoreUnimportantViews", {
    get: function(){ return this.settings._ignoreViews; },
    set: function(value) {
      this.settings._ignoreViews = value;
      this.proxy(["compressedLayoutHierarchy", {compressLayout: this.settings._ignoreViews}], someCallback);}
});

this.settings.ignoreUnimportantViews = this.args. ignoreUnimportantViews || false;
```