lang/org: pretty symbols for old and new style

org-mode recently changed the standard for naming blocks.
Previously, it would use capitalized names; now it uses lower case
names.

E.g., #+BEGIN_SRC -> #+begin_src

Also, add a "quote" symbol for the #+begin_quote block.

modules/ui/pretty-code/config.el

@@ -5,6 +5,8 @@
     :name          "»"
     :src_block     "»"
     :src_block_end "«"
+    :quote         "“"
+    :quote_end     "”"
     ;; Functional
     :lambda        "λ"
     :def           "ƒ"