Add editorconfig from Hydrogen

.editorconfig

+
+# top-most EditorConfig file
+root = true
+
+# Unix-style newlines with a newline ending every file
+[*]
+end_of_line = lf
+insert_final_newline = true
+charset = utf-8
+indent_style = space
+indent_size = 4
+
+# Matches multiple files with brace expansion notation
+# Set default charset
+# [*.{js,py}]