Update projects to Xamarin.Forms 1.3.0.6292
Merge remote-tracking branch 'origin/master'

Conflicts:
	Samples/XLabs.Sample.WP/XLabs.Sample.WP.csproj

	src/Forms/Charting/XLabs.Forms.Charting.Droid/XLabs.Forms.Charting.Droid.csproj

	src/Forms/Charting/XLabs.Forms.Charting.WP/XLabs.Forms.Charting.WP.csproj
	src/Forms/XLabs.Forms.Droid/XLabs.Forms.Droid.csproj
	src/Forms/XLabs.Forms.WP8/XLabs.Forms.WP8.csproj