Added OnNavigating event
Forgotten file
Switched event from Uri to EventArgs<Uri>
Fix after last change
Modal Support

Turns out the only way to have a fully awaitable dialog is to do some
fairly nasty stuff with the android message pump.  I didn't even look at
iOS.

Rather than chase that I've implemented a class that encapsulates a
pattern for using dialogs that is fairly clean.
Removed excess comment line
Xaml based Validation.

Xmal base validation.  Allows for mutliple validation sets per page and
unlimted rules/actions.
I'll be cleaning it up a bit and adding more validators, but the overall
design is stable.
Added more validators and enhanced the ValidationRule
More Validators

Added MinLength,MaxLength,AlphaOnly,AlphaNumeric
Gesture Sample in place

Added iOS support for gestures.  A few issues there that I'll dig into.
(Longpress not firing and swiping seemingly non existant, both of which
could be caused by me running emulator only....)
Android is complete.
Added a second gesture area to the sample

Occurred to me that folks might think you could only attach gestures to
one view within a GestureContentViews children, added a second gesture
area with different gesture support to make it plain :dancer:
Validator sample page

Added triggers to ValidatorActions, the sample shows how to use them.
:dart:
Updated Sample

Simplified the Xaml layout and how rules trigger rule specific actions.
Refactoring ++

Refactored the Validation code into the Validation Namespace
Added PropertySetters to Action
Added the ability for the user to supply custom validators at runtime
Renamed classes to make Xaml cleaner
validation sample showing all the validators

Next up...validator documentation.   I think I should tackle that doc
first since this is the most complex component I've put in thus far.
Added class diagram
Added CarouselView Sample
ScreenShots
Merge pull request #473 from sami1971/master

System serializer fix + fix for HybridWebView size
Merge pull request #455 from halkar/onnavigating-event

Added OnNavigating event
Added NumericOnly Validator