The txt files are now installed into doc directory, and a few of them were missing.
The txt files are now installed into doc directory, and a few of them were
missing.

--HG--
branch : HEAD

jkerihuel/dovecot,dscho/dovecot,jwm/dovecot-notmuch,dscho/dovecot,jwm/dovecot-notmuch,jkerihuel/dovecot,jkerihuel/dovecot,jwm/dovecot-notmuch,jwm/dovecot-notmuch,jwm/dovecot-notmuch,dscho/dovecot,jkerihuel/dovecot,dscho/dovecot,jkerihuel/dovecot,dscho/dovecot