pgAdmin3 doc location

Hi Dave,
I've seen you just added options-tab doc under en_US/*.html.
I wanted to comment on doc location before, just forgot to do it. I
think making the location for application documentation doesn't make
sense, because each version of the binary should be packed with the
exact matching doc version. Therefore, only one version is needed.
On the other side, if the doc location is well-known to us, we could
easily switch directories to the best matching language version
(fall-back language will be of course en_US). Additionally, if we switch
to a different format (e.g. HTML workstop) to support search and index,
upgrading the setting wouldn't be possible anyway.

Regards,
Andreas