Add .editorconfig

.editorconfig

@@ -0,0 +1,16 @@
+# http://editorconfig.org/
+
+root = true
+
+[*]
+charset = utf-8
+end_of_line = lf
+insert_final_newline = true
+trim_trailing_whitespace = true
+
+[*.{hpp,inl,cpp,lua}]
+indent_style = tab
+
+[*.html]
+indent_size = 4
+indent_style = space