fix: Allow the launcher to run on clean Windows 7 and 10

Author: twpol

Source/Launcher/Launcher.csproj

@@ -9,10 +9,9 @@
     <AppDesignerFolder>Properties</AppDesignerFolder>
     <RootNamespace>ORTS</RootNamespace>
     <AssemblyName>OpenRails</AssemblyName>
-    <TargetFrameworkVersion>v4.7.2</TargetFrameworkVersion>
+    <TargetFrameworkVersion>v2.0</TargetFrameworkVersion>
     <FileAlignment>512</FileAlignment>
     <ApplicationIcon>..\ORTS.ico</ApplicationIcon>
-    <TargetFrameworkProfile />
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)' == 'Debug|AnyCPU'">
     <DebugSymbols>true</DebugSymbols>
@@ -24,7 +23,6 @@
     <WarningLevel>4</WarningLevel>
     <LangVersion>7.3</LangVersion>
     <PlatformTarget>AnyCPU</PlatformTarget>
-    <Prefer32Bit>false</Prefer32Bit>
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)' == 'Release|AnyCPU'">
     <DebugType>pdbonly</DebugType>
@@ -36,7 +34,6 @@
     <DocumentationFile>..\..\Program\OpenRails.xml</DocumentationFile>
     <NoWarn>1591</NoWarn>
     <LangVersion>7.3</LangVersion>
-    <Prefer32Bit>false</Prefer32Bit>
   </PropertyGroup>
   <PropertyGroup>
     <ApplicationManifest>..\Launcher\app.manifest</ApplicationManifest>

Source/Launcher/app.config

@@ -1,3 +1,7 @@
-<?xml version="1.0" encoding="utf-8"?>
+<?xml version="1.0"?>
 <configuration>
-<startup><supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.7.2"/></startup></configuration>
+  <startup>
+    <supportedRuntime version="v4.0"/>
+    <supportedRuntime version="v2.0.50727"/>
+  </startup>
+</configuration>