Add release notes for 0.9.5

(cherry picked from commit e4e4b1d4231d1d2594558dcacd8429e59853f8ec)
scripts: Improve the 'addsite' command

- The -L option (symlinking) is now enabled by default
- New option -T (for setting the target dir, defaults to $PWD)
- New option -H (site hostname)

A site's hostname now default to <sitename>.dev, to avoid confusion
between the site name and the site's hostname.