decrease the version of .net standard, from 1.3 to 1.1

Author: oldrev

GeographicLib/Sandwych.GeographicLib.csproj

@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFrameworks>netstandard1.3;net461</TargetFrameworks>
+    <TargetFrameworks>netstandard1.1;net45</TargetFrameworks>
     <LangVersion>latest</LangVersion>
     <RootNamespace>GeographicLib</RootNamespace>
   </PropertyGroup>