Make Roslyn Analyzers opt-in at compile-time (resolves #1813)

They are still run by the IDE at design-time. To opt-in, set the MSBuild
property MachineRunAnalyzersDuringBuild. From the command-line, you can do this
by adding `/p:MachineRunAnalyzersDuringBuild=true`.

BizHawk.Common/BizHawk.Common.csproj

@@ -8,8 +8,8 @@
 	<ItemGroup>
 		<PackageReference Include="System.ComponentModel.Annotations" Version="4.7.0" PrivateAssets="All" />
 		<PackageReference Include="System.Reflection.Emit.Lightweight" Version="4.7.0" PrivateAssets="All" />
-	</ItemGroup>
-	<ItemGroup>
+		<PackageReference Include="StyleCop.Analyzers" Version="1.2.0-beta.113"
+			Condition=" '$(MachineRunAnalyzersDuringBuild)' != '' " />
 		<Compile Include="$(SolutionDir)Version/svnrev.cs" />
 		<Compile Include="$(SolutionDir)Version/VersionInfo.cs" />
 		<Compile Remove="Extensions/BinaryReaderExtensions.cs" />

Common.props

@@ -6,6 +6,8 @@
 		<LangVersion>8.0</LangVersion>
 		<OutputPath>$(SolutionDir)output/dll</OutputPath>
 		<PlatformTarget>x64</PlatformTarget>
+		<RunAnalyzersDuringBuild Condition=" '$(MachineRunAnalyzersDuringBuild)' == '' ">false</RunAnalyzersDuringBuild>
+		<RunCodeAnalysis>false</RunCodeAnalysis>
 	</PropertyGroup>
 	<PropertyGroup Condition=" '$(Configuration)' == 'Debug' ">
 		<DebugSymbols>true</DebugSymbols>
@@ -21,6 +23,5 @@
 	</PropertyGroup>
 	<ItemGroup>
 		<AdditionalFiles Include="$(SolutionDir).stylecop.json" />
-		<PackageReference Include="StyleCop.Analyzers" Version="1.2.0-beta.113" PrivateAssets="All" />
 	</ItemGroup>
 </Project>

Dist/BuildAndPackage.bat

@@ -14,7 +14,7 @@ for /f "usebackq tokens=*" %%A in (`vswhere -version "[16.0,17.0)" -requires Mic
 IF "%MSBUILDPATH%"=="" GOTO MISSINGMSBUILD
 
 nuget restore ..\BizHawk.sln
-call "%MSBUILDPATH%" ..\BizHawk.sln /p:Configuration=Release /p:Platform="Any Cpu" /t:rebuild
+call "%MSBUILDPATH%" ..\BizHawk.sln "/p:Configuration=Release;Platform=AnyCPU;MachineRunAnalyzersDuringBuild=true" /t:rebuild
 
 @if errorlevel 1 goto MSBUILDFAILED