add editorconfig for golang code

.editorconfig

@@ -0,0 +1,25 @@
+# http://editorconfig.org/
+
+root = true
+
+# Unix-style newlines with a newline ending every file
+[*]
+charset = utf-8
+indent_style = tab
+indent_size = 4
+insert_final_newline = true
+trim_trailing_whitespace = true
+
+[*.json]
+charset = utf-8
+indent_style = space
+indent_size = 2
+insert_final_newline = true
+trim_trailing_whitespace = true
+
+[*.yaml, *.yml]
+charset = utf-8
+indent_style = space
+indent_size = 2
+insert_final_newline = true
+trim_trailing_whitespace = true