Add ModuleDefinition.ImmediateRead

We are going to use this to do a multi stage load in parallel.  We will be able to greatly reduce our load times using this new API.  The way it's going to work is

Stage 1 - In parallel, load the assemblies with ReadingMode.Deferred.
Stage 2 - Populate our AssemblyResolver with a cache of all read assemblies.
Stage 3 - In parallel, call ImmediateRead.

What I really want is an API to load everything in stage 3.  I found that ImmediateRead does not load method bodies.  I don't know if/how you want want something like this exposed via the public API.  For now I'm iterating the data model and forcing things to load that ImmediateRead did not cover.

Mono.Cecil/AssemblyReader.cs

@@ -166,6 +166,7 @@ protected override void ReadModule ()
 
 		public void ReadModule (ModuleDefinition module, bool resolve_attributes)
 		{
+			module.ReadingMode = ReadingMode.Immediate;
 			this.resolve_attributes = resolve_attributes;
 
 			if (module.HasAssemblyReferences)

Mono.Cecil/ModuleDefinition.cs

@@ -921,6 +921,12 @@ public IMetadataTokenProvider LookupToken (MetadataToken token)
 		{
 			return Read (token, (t, reader) => reader.LookupToken (t));
 		}
+
+		public void ImmediateRead()
+		{
+			var moduleReader = new ImmediateModuleReader(Image);
+			moduleReader.ReadModule (this, resolve_attributes: true);
+		}
 
 		readonly object module_lock = new object();
 

Test/Mono.Cecil.Tests/ModuleTests.cs

@@ -277,6 +277,17 @@ public void OpenModuleDeferred ()
 			}
 		}
 
+
+		[Test]
+		public void OpenModuleDeferredAndThenPerformImmediateRead ()
+		{
+			using (var module = GetResourceModule ("hello.exe", ReadingMode.Deferred)) {
+				Assert.AreEqual (ReadingMode.Deferred, module.ReadingMode);
+				module.ImmediateRead();
+				Assert.AreEqual (ReadingMode.Immediate, module.ReadingMode);
+			}
+		}
+
 		[Test]
 		public void OwnedStreamModuleFileName ()
 		{