Implement cross-platform improvements from master

Contains fixes rebased from d2afe06 ... 9f4dcb6

BepInEx.Core/Console/Windows/ConsoleEncoding/ConsoleEncoding.PInvoke.cs

@@ -0,0 +1,51 @@
+// --------------------------------------------------
+// UnityInjector - ConsoleEncoding.PInvoke.cs
+// Copyright (c) Usagirei 2015 - 2015
+// --------------------------------------------------
+
+using System;
+using System.Runtime.InteropServices;
+
+namespace UnityInjector.ConsoleUtil
+{
+	// --------------------------------------------------
+	// Code ported from
+	// https://gist.github.com/asm256/9bfb88336a1433e2328a
+	// Which in turn was seemingly ported from
+	// http://jonskeet.uk/csharp/ebcdic/
+	// using only safe (managed) code
+	// --------------------------------------------------
+	internal partial class ConsoleEncoding
+	{
+		[DllImport("kernel32.dll")]
+		private static extern uint GetConsoleOutputCP();
+
+		[DllImport("kernel32.dll")]
+		private static extern uint GetACP();
+
+		[DllImport("kernel32.dll", SetLastError = true)]
+		private static extern int MultiByteToWideChar(
+			uint codePage,
+			uint dwFlags,
+			[In, MarshalAs(UnmanagedType.LPArray)] byte[] lpMultiByteStr,
+			int cbMultiByte,
+			[Out, MarshalAs(UnmanagedType.LPWStr)]
+			char[] lpWideCharStr,
+			int cchWideChar);
+
+		[DllImport("kernel32.dll")]
+		private static extern IntPtr SetConsoleOutputCP(uint codepage);
+
+		[DllImport("kernel32.dll", SetLastError = true)]
+		private static extern int WideCharToMultiByte(
+			uint codePage,
+			uint dwFlags,
+			[In, MarshalAs(UnmanagedType.LPWStr)] char[] lpWideCharStr,
+			int cchWideChar,
+			[Out, MarshalAs(UnmanagedType.LPArray)]
+			byte[] lpMultiByteStr,
+			int cbMultiByte,
+			IntPtr lpDefaultChar,
+			IntPtr lpUsedDefaultChar);
+	}
+}