Isolated API definitions to their own library

src/Discord.Net.Core/Utils/Optional.cs

@@ -1,55 +0,0 @@
-using System;
-using System.Diagnostics;
-
-namespace Discord
-{
-    //Based on https://github.com/dotnet/coreclr/blob/master/src/mscorlib/src/System/Nullable.cs
-    [DebuggerDisplay(@"{DebuggerDisplay,nq}")]
-    public struct Optional<T>
-    {
-        public static Optional<T> Unspecified => default(Optional<T>);
-        private readonly T _value;
-
-        /// <summary> Gets the value for this paramter. </summary>
-        public T Value
-        {
-            get
-            {
-                if (!IsSpecified)
-                    throw new InvalidOperationException("This property has no value set.");
-                return _value;
-            }
-        }
-        /// <summary> Returns true if this value has been specified. </summary>
-        public bool IsSpecified { get; }
-
-        /// <summary> Creates a new Parameter with the provided value. </summary>
-        public Optional(T value)
-        {
-            _value = value;
-            IsSpecified = true;
-        }
-
-        public T GetValueOrDefault() => _value;
-        public T GetValueOrDefault(T defaultValue) => IsSpecified ? _value : defaultValue;
-
-        public override bool Equals(object other)
-        {
-            if (!IsSpecified) return other == null;
-            if (other == null) return false;
-            return _value.Equals(other);
-        }
-        public override int GetHashCode() => IsSpecified ? _value.GetHashCode() : 0;
-
-        public override string ToString() => IsSpecified ? _value?.ToString() : null;
-        private string DebuggerDisplay => IsSpecified ? (_value?.ToString() ?? "<null>") : "<unspecified>";
-
-        public static implicit operator Optional<T>(T value) => new Optional<T>(value);
-        public static explicit operator T(Optional<T> value) => value.Value;
-    }
-    public static class Optional
-    {
-        public static Optional<T> Create<T>() => Optional<T>.Unspecified;
-        public static Optional<T> Create<T>(T value) => new Optional<T>(value);
-    }
-}