[MERGE] remove out-of-date options from Windows standalone installer.

[Mark Hammond]

> This patch removes out-of-date options from Windows installer.
> 
> 1) Shell context menu was my unsuccessful attempt to reimplement
> something similar to Cygwin's Bash Here context menu. I made it off by
> default many months ago in hope that one day I'll remove it completely.
> I believe nobody used it actually because nobody complain about its
> misbehaving.
> 
> 2) Link to Bazaar Survey is removed because survey itself is out of
> date.

Thanks Alex,

bb:approve from me, fwiw

Mark