Moving corlib files out of "System" directory into root

BeefLibs/corlib/src/Nullable.bf

@@ -0,0 +1,102 @@
+using System.Reflection;
+using System.Collections.Generic;
+using System.Runtime.CompilerServices;
+using System.Diagnostics;
+
+namespace System
+{
+    public struct Nullable<T> where T : struct
+    {
+		#region Sync with runtime code
+		internal T mValue;
+        internal bool mHasValue;
+		#endregion
+
+		public this(T value)
+        {
+            mHasValue = true;
+            mValue = value;
+        }
+        
+        public bool HasValue
+        {
+            get { return mHasValue; }
+        }
+        
+        public T Value
+        {
+            get
+            {
+            	Debug.Assert(mHasValue, "Value cannot be retrieved on a null nullable.");
+                return mValue;
+            }
+        }
+
+		public ref T ValueRef
+		{
+		    get mut
+		    {
+				Debug.Assert(mHasValue, "Value cannot be retrieved on a null nullable.");
+		        return ref mValue;
+		    }
+		}
+        
+        /*public override bool Equals(object other)
+        {
+            if (other == null)
+                return mHasValue == false;
+            if (!(other is Nullable<T>))
+                return false;
+            
+            return Equals((Nullable<T>)other);
+        }
+        
+        bool Equals(Nullable<T> other)
+        {
+            if (other.mHasValue != mHasValue)
+                return false;
+            
+            if (mHasValue == false)
+                return true;
+            
+            return other.mValue.Equals(mValue);
+        }*/
+        
+        /*public override int GetHashCode()
+        {
+            if (!mHasValue)
+                return 0;
+            
+            return mValue.GetHashCode();
+        }*/
+        
+        public T GetValueOrDefault()
+        {
+            return mValue;
+        }
+        
+        public T GetValueOrDefault(T defaultValue)
+        {
+            return mHasValue ? mValue : defaultValue;
+        }
+        
+        public override void ToString(String str)
+        {
+            if (mHasValue)
+                mValue.ToString(str);
+            else
+                str.Clear();
+        }
+        
+        public static implicit operator Nullable<T>(T value)
+        {
+            return Nullable<T>(value);
+        }
+        
+        public static explicit operator T(Nullable<T> value)
+        {
+			Debug.Assert(value.mHasValue, "Value cannot be retrieved on a null nullable.");
+            return value.mValue;
+        }
+    }
+}