Update Scintilla struct declarations. Fixes #76

Sci_Position.h

@@ -0,0 +1,29 @@
+// Scintilla source code edit control
+/** @file Sci_Position.h
+ ** Define the Sci_Position type used in Scintilla's external interfaces.
+ ** These need to be available to clients written in C so are not in a C++ namespace.
+ **/
+// Copyright 2015 by Neil Hodgson <neilh@scintilla.org>
+// The License.txt file describes the conditions under which this software may be distributed.
+
+#ifndef SCI_POSITION_H
+#define SCI_POSITION_H
+
+#include <stddef.h>
+
+// Basic signed type used throughout interface
+typedef ptrdiff_t Sci_Position;
+
+// Unsigned variant used for ILexer::Lex and ILexer::Fold
+typedef size_t Sci_PositionU;
+
+// For Sci_CharacterRange which is defined as long to be compatible with Win32 CHARRANGE
+typedef long Sci_PositionCR;
+
+#ifdef _WIN32
+ #define SCI_METHOD __stdcall
+#else
+ #define SCI_METHOD
+#endif
+
+#endif