Fix for types - isString and isNumber.
Modified several tests to pass on VS Emulator for Android.
Fix page background to be applied in onLoaded method.
Enhancements for dependency-observable - it is now possible to add defaultValueGetter function to extract default value for a property. It can also be cached or not.
Remove android_constants because they are per theme and we cannot use them safely.
Fix for SearchBar reseColorProperty method.
This is the default location when installing from npm, and Angular uses
that when parsing CSS.
Updated module paths, requires, csproj, tsconfig and grunt tasks.
