Add option to install and start Visual Studio 2015

Use VsixTesting.Installer and launchSettings.json to create an option
to install and start Visual Studio 2015.

GitHubVS.sln

@@ -131,6 +131,8 @@ Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "ReactiveUI.Testing", "submo
 EndProject
 Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "ReactiveUI.Wpf", "submodules\reactiveui\src\ReactiveUI.Wpf\ReactiveUI.Wpf.csproj", "{E899B03C-6E8E-4375-AB65-FC925D721D8B}"
 EndProject
+Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "InstallAndStart", "test\Launcher\InstallAndStart.csproj", "{79F32BE1-2764-4DBA-97F6-21053DE44270}"
+EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|Any CPU = Debug|Any CPU
@@ -530,6 +532,16 @@ Global
 		{E899B03C-6E8E-4375-AB65-FC925D721D8B}.Release|Any CPU.Build.0 = Release|Any CPU
 		{E899B03C-6E8E-4375-AB65-FC925D721D8B}.ReleaseWithoutVsix|Any CPU.ActiveCfg = Release|Any CPU
 		{E899B03C-6E8E-4375-AB65-FC925D721D8B}.ReleaseWithoutVsix|Any CPU.Build.0 = Release|Any CPU
+		{79F32BE1-2764-4DBA-97F6-21053DE44270}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{79F32BE1-2764-4DBA-97F6-21053DE44270}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{79F32BE1-2764-4DBA-97F6-21053DE44270}.DebugCodeAnalysis|Any CPU.ActiveCfg = Debug|Any CPU
+		{79F32BE1-2764-4DBA-97F6-21053DE44270}.DebugCodeAnalysis|Any CPU.Build.0 = Debug|Any CPU
+		{79F32BE1-2764-4DBA-97F6-21053DE44270}.DebugWithoutVsix|Any CPU.ActiveCfg = Debug|Any CPU
+		{79F32BE1-2764-4DBA-97F6-21053DE44270}.DebugWithoutVsix|Any CPU.Build.0 = Debug|Any CPU
+		{79F32BE1-2764-4DBA-97F6-21053DE44270}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{79F32BE1-2764-4DBA-97F6-21053DE44270}.Release|Any CPU.Build.0 = Release|Any CPU
+		{79F32BE1-2764-4DBA-97F6-21053DE44270}.ReleaseWithoutVsix|Any CPU.ActiveCfg = Release|Any CPU
+		{79F32BE1-2764-4DBA-97F6-21053DE44270}.ReleaseWithoutVsix|Any CPU.Build.0 = Release|Any CPU
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE

nuget.config

@@ -2,7 +2,8 @@
 <configuration>
   <packageSources>
     <add key="nuget.org" value="https://www.nuget.org/api/v2/" />
-	<add key="dotnet-core" value="https://dotnet.myget.org/F/dotnet-core/api/v3/index.json" />
+    <add key="dotnet-core" value="https://dotnet.myget.org/F/dotnet-core/api/v3/index.json" />
+    <add key="vsixtesting" value="https://www.myget.org/F/vsixtesting/api/v3/index.json" />
     <add key="Custom Packages for GHfVS" value="lib" />
   </packageSources>
   <activePackageSource>

test/Launcher/InstallAndStart.csproj

@@ -0,0 +1,11 @@
+<Project Sdk="Microsoft.NET.Sdk">
+  <PropertyGroup>
+    <TargetFramework>net461</TargetFramework>
+  </PropertyGroup>
+  <ItemGroup>
+    <PackageReference Include="VsixTesting.Installer" Version="0.1.36-beta-g2c36f902a0" />
+  </ItemGroup>
+  <ItemGroup>
+    <ProjectReference Include="..\..\src\GitHub.VisualStudio\GitHub.VisualStudio.csproj" />
+  </ItemGroup>
+</Project>

test/Launcher/Properties/launchSettings.json

@@ -0,0 +1,12 @@
+{
+  "profiles": {
+    "Visual Studio 2015": {
+      "executablePath": "$(VsixTestingInstallerPath)",
+      "commandLineArgs": "/ApplicationPath \"C:\\Program Files (x86)\\Microsoft Visual Studio 14.0\\Common7\\IDE\\devenv.exe\" /RootSuffix Exp /InstallAndStart \"$(SolutionDir)\\build\\$(Configuration)\\GitHub.VisualStudio.vsix\""
+    },
+    "Visual Studio 2017": {
+      "executablePath": "$(DevEnvDir)devenv.exe",
+      "commandLineArgs": "/rootsuffix Exp /log"
+    }
+  }
+}