Updated Enyo framework to 2.4.0-pre.2
Added splashscreen / back button functionality to Enyo

Previously, the Enyo implementations were not listening to the back button
events and would not close the splashscreen on iOS devices.

Fixes #203
Updated CSS rules for toolbar in Enyo
Improved look of app in Enyo

+ Reduced height of list items
+ Prevented image from being stretched
+ Simplified some CSS rules
Fixes "Load more..." button in Enyo

Button was not being displayed previously.
Updated enyo package configuration
Automated PhoneGap Builds scripts support custom email addresses

This enables other people in the community to use the build scripts we have provided with their own PhoneGap Build Adobe accounts.
Merge pull request #271 from matthewdunsdon/enyo-iu-improvement

Enyo UI improvements
Merge pull request #273 from matthewdunsdon/custom-phonegap-build-email-option

Automated PhoneGap Builds scripts to support custom email addresses
Updated Xamarin assets
Cleaned up Xamarin project files
Updated icons and layout for Window Phone 8 in Xamarin
Added placeholder icon for Android on Xamarin