[ticket/11528] Move $client into functional_test_case

PHPBB3-11528
[ticket/11528] Move $already_installed into parent class

PHPBB3-11528
[ticket/11528] Start session if not started

PHPBB3-11528
[ticket/11528] Add initial test class for ui tests

PHPBB3-11528
[ticket/11528] Configure travis for zombiejs-nodejs-npm

PHPBB3-11528
[ticket/11528] Add sample test

PHPBB3-11528
[ticket/11528] Add NODE_PATH to env

PHPBB3-11528
[ticket/11528] Dont start multiple sessions

PHPBB3-11528
[ticket/11528] Use selectOption instead of setValue for select fields

PHPBB3-11528
[ticket/11528] Add findById('main') to check page text

PHPBB3-11528
[ticket/11528] Fixed "jQuery is not defined error"

PHPBB3-11528
[ticket/11528] Add UI tests to DB=mysql

PHPBB3-11528
[ticket/11528] Reset session post installation

PHPBB3-11528
[ticket/11528] Add UI tests to all phpunit-$DB-travis.xml

PHPBB3-11528