add editorconfig

common/.editorconfig

@@ -0,0 +1,17 @@
+# EditorConfig is awesome: http://EditorConfig.org
+
+# top-most EditorConfig file
+root = true
+
+# Unix-style newlines with a newline ending every file
+[*]
+end_of_line = lf
+insert_final_newline = true
+
+# Matches multiple files with brace expansion notation
+# Set default charset
+[{include,lib,tests}/**.{c,h,proto,cpp,hpp,h.in,hpp.in}]
+charset = utf-8
+indent_style = tab
+indent_size = 8
+trim_trailing_whitespace=true