[C] make Application ctor public (#2020)

- fixes #2018

Xamarin.Forms.Core/Application.cs

@@ -23,7 +23,7 @@ namespace Xamarin.Forms
 
 		static SemaphoreSlim SaveSemaphore = new SemaphoreSlim(1, 1);
 
-		protected Application()
+		public Application()
 		{
 			var f = false;
 			if (f)

docs/Xamarin.Forms.Core/Xamarin.Forms/Application.xml

@@ -26,8 +26,8 @@
   </Docs>
   <Members>
     <Member MemberName=".ctor">
-      <MemberSignature Language="C#" Value="protected Application ();" />
-      <MemberSignature Language="ILAsm" Value=".method familyhidebysig specialname rtspecialname instance void .ctor() cil managed" />
+      <MemberSignature Language="C#" Value="public Application ();" />
+      <MemberSignature Language="ILAsm" Value=".method public hidebysig specialname rtspecialname instance void .ctor() cil managed" />
       <MemberType>Constructor</MemberType>
       <AssemblyInfo>
         <AssemblyVersion>1.3.0.0</AssemblyVersion>