Update src/winphone/ChildBrowserCommand.cs

Fix: Invalid character in succes callback
Added: The childbrowser close-callback
Update www/winphone/ChildBrowser.js

Fix: Only call event when is assigned
Added: Handle close event
Merge pull request #25 from MaartenR35/patch-1

Update src/winphone/ChildBrowserCommand.cs
Merge pull request #27 from MaartenR35/patch-3

Update www/winphone/ChildBrowser.js
[js] only openExternal for Android

thanks @jbatchelor
Update src/ios/ChildBrowserCommand.m

a little bug fixed@ line:43 from childBrowser to self.childBrowser
Merge pull request #30 from fattomhk/patch-1

fixing childBrowser controller reference in ChildBrowserCommand
[ios][2.3.0] add plugin to config.xml for 2.3.0+