Link to info manual in `defgroup'.

Link to info manual in `defgroup'.

* lisp/progmodes/ada-mode.el (ada):
* lisp/woman.el (woman): Link to info manual and Commentary section.

* lisp/url/url-vars.el (url):
* lisp/erc/erc.el (erc):
* lisp/progmodes/flymake.el (flymake):
* lisp/nxml/nxml-mode.el (nxml):
* lisp/net/eww.el (eww):
* lisp/speedbar.el (speedbar, speedbar-faces, speedbar-vc):
* lisp/htmlfontify.el (htmlfontify):
* lisp/ses.el (ses):
* lisp/epa.el (epa):
* lisp/ido.el (ido): Link to info manual.