Returns the corresponding Cordova o Phonegap object.
If it's not present returns null, this is the case, for example, of a WebApp.
The method performs the following testing:
if ("PhoneGap" in window)
return window.PhoneGap;
else if ("cordova" in window)
return window.cordova;
else
return null;
Quick example
if (mui.cordovaAvailable()) {
var o = mui.cordova();
...
}