Adds support for preserving all module initializers. Without this, only one of the module initializers appears in the merged assembly because of deduplication.

• Adds separate step to handle module initializers
• Renames module initializer methods to unique name (prefixed with fully qualified assembly name)
• Generates new <Module> class where its static constructor calls all module initializers found in merged assemblies

Fixes #312.

Example of merged module initializers (decompiled by ILSpy):

internal class <Module>
{
	static <Module>()
	{
		AnotherClassLibrary_Version_1.0.2.0_Culture_neutral_PublicKeyToken_null_ModuleInitializer();
		ClassLibrary_Version_1.0.2.0_Culture_neutral_PublicKeyToken_null_ModuleInitializer();
		WPFThemingAndLibraryStyles_Version_1.0.2.0_Culture_neutral_PublicKeyToken_null_ModuleInitializer();
	}

	private static void WPFThemingAndLibraryStyles_Version_1.0.2.0_Culture_neutral_PublicKeyToken_null_ModuleInitializer()
	{
		Program.InitializerOne();
		Program.InitializerTwo();
	}

	private static void AnotherClassLibrary_Version_1.0.2.0_Culture_neutral_PublicKeyToken_null_ModuleInitializer()
	{
		OtherModuleInitializer.Initialize();
	}

	private static void ClassLibrary_Version_1.0.2.0_Culture_neutral_PublicKeyToken_null_ModuleInitializer()
	{
		ModuleInitializer.Initialize();
	}
}

Notes

• In general, once compiled, all methods of an assembly annotated with [ModuleInitializer] are merged into a namespace-less class named <Module>. Its static constructor calls all methods annotated with [ModuleInitializer] of its module. Therefore, only one type/method must be considered per module when ILRepack merges assemblies.

Tests

Currently, I tested this feature by temporary adding some module initializers to existing projects and verify them with ILSpy/by running the applications. So, as of now, those changes is not part of the PR!

So the question is:
Should there be an additional set of integration scenario projects added to explicitly test merging modules, or should some existing projects be adapted to also test for module initializers being merged and working?v