add LineEndings module

src/core/LineEndings.h

@@ -0,0 +1,20 @@
+#ifndef LINEENDINGS_H
+#define LINEENDINGS_H
+
+#include "Span.h"
+
+class LineEndings
+{
+public:
+    enum Type
+    {
+        LF,
+        CRLF,
+        CR,
+        COUNT,
+    };
+
+    static const Span spans[COUNT];
+};
+
+#endif