Add .editorconfig file.

Config file to help define the code style for supported editors and IDEs.
http://editorconfig.org

.editorconfig

@@ -0,0 +1,13 @@
+; This file is for unifying the coding style for different editors and IDEs.
+; More information at http://editorconfig.org
+
+root = true
+
+[*]
+indent_style = tab
+end_of_line = lf
+insert_final_newline = true
+trim_trailing_whitespace = true
+
+[*.bat]
+end_of_line = crlf