Add support for C# Delegates

[Joshua2000B]

C# delegates are currently not collected. The are essentially defining a function pointer in C# - need to discuss how to categorize them.

public delegate void LogMessage(string message);

public static void LogToConsole(string text) => Console.WriteLine($"Console: {text}");
public static void LogToFile(string text) => System.IO.File.WriteAllText("log.txt", text);

// Instantiate the delegate by assigning a method group
LogMessage logger = LogToConsole;

// Invoke the method through the delegate variable
logger("Application started."); 

// Dynamically change the method target at runtime
logger = LogToFile;
logger("An error occurred.");

[Joshua2000B]

On further thought, this is similar to a C++ typedef for a function pointer (as mentioned in #67). They will be collected the same way.

[Joshua2000B]

Initial support for this has been added in 8496dbe. However, currently we do no correctly handle delegate lambdas:

Del d = delegate(int k) {}

This is because they are marked as <delegate><name>delegate</name>...</delegate>. They should be marked as a lambda instead.