Import a simple text editor I started working on.

Editor/main.cpp

@@ -0,0 +1,19 @@
+#include "Document.h"
+#include "Editor.h"
+#include <stdio.h>
+
+int main(int c, char** v)
+{
+    std::string file_to_open = "cuki.h";
+    if (c > 1) {
+        file_to_open = v[1];
+    }
+    auto document = Document::create_from_file(file_to_open);
+    if (!document) {
+        fprintf(stderr, "Failed to open file.\n");
+        return 1;
+    }
+    Editor editor;
+    editor.set_document(std::move(document));
+    return editor.exec();
+}