ikiwiki hosting internals/ todo/ do not enable mod_userdir just so we can disable it

ikiwiki-hosting-web.postinst does `a2enmod userdir` so that it can use `UserDir disabled`. This seems a little silly.

My `ready/userdir` branch fixes that.

http://git.pseudorandom.co.uk/smcv/ikiwiki-hosting.git/commitdiff/refs/heads/ready/userdir

--smcv

> What about upgrades?

> Anyway, I think that the idea here was to make the confuration work even if used alongside an apache that did have userdir configured for other sites. --Joey

> > Look at the patch, I think I already addressed both objections :-)

> > There are two changes:

> > - don't force mod_userdir on in the postinst; upgrades unaffected.
> > - wrap the `UserDir disabled` directive in `<IfModule mod_userdir.c>`, so that if it's loaded, we disable it, but if it isn't, we do nothing. Upgraded machines (and machines where the sysadmin wants userdirs on another vhost) will load mod_userdir, but disable it for ikisite-managed vhosts; new installations won't need to load it at all.

> > --smcv

> > > merged --Joey