[mythtvnz] Problems with backend and mythweb after upgrading to Ubuntu 15.04

[Mark]

I upgraded my Mythbuntu install from 14.04 to 15.04 yesterday and have
run into a couple of problems that might interest people.

1) Due to the change to systemd Mythtv doesn't auto start after boot.
  I'm currently manually starting it using sudo systemctl start
mythtv-backend

2) Mythweb failed with an unhelpful error in the log  'PHP Fatal error:
Call to a member function query_col' which is usually related to having
an incorrect password configured.  In this case though it seems to be
caused by too low a php memory_limit set
in /etc/apache2/sites-enabled/mythweb.conf

I changed the old default from 32M to the new default of 64M and it now
works.  The configuration line now reads as

          php_value memory_limit                  64M

Regards
Mark