StatusBar Plugin API Audit

We need to audit the API and features of the statusbar plugin. Then we can define exactly what we will implement, and make sure that the docs, and all relevant platforms have equal support.

Here is some background on why the statusbar plugin is a thing:
http://markmail.org/message/pfyzgyv667h573or

The statusbar is currently supported on iOS and Android. I could easily add it to WP8 as there is a simple native API for this.

There is also a preference (bool) called 'Fullscreen'. This will hide the statusbar at startup on Android / WP8 and possible other platforms but it is NOT available on iOS. The documentation, however says it is available everywhere:
http://cordova.apache.org/docs/en/3.4.0/config_ref_index.md.html#The%20config.xml%20File

The origin of the 'fullscreen' preference appears to be from phonegap/build:
http://docs.build.phonegap.com/en_US/3.3.0/configuring_preferences.md.html#Preferences

The statusbar (iOS) plugin doc states how to hide the statusbar at startup, but it is apparently not yet doable from a preference.
https://github.com/apache/cordova-plugins/tree/master/statusbar

Ultimately we need to resolve all of this mess down to a consistent implementation, and most likely also promote the statusbar plugin to it's own repo.