1.3.5 -> 1.4.0 Upgrade fixes

| Q             | A
| ------------- | ---
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | -
| Refs tickets  | #1620
| License       | MIT
| Doc PR        | -

There is still a bug remaining that I cannot fix. After the upgrade is complete, the regeneration of the session is failing and throwing an error (see below).

I would like this pulled despite the error as It is not related to this fix anyway. I was hoping that Christian @cmfcmf could take a look at the other error.

> Upgrade Results:

> ZikulaExtensionsModule upgraded
ZikulaBlocksModule upgraded
ZikulaThemeModule upgraded
ZikulaSettingsModule upgraded
ZikulaCategoriesModule upgraded
ZikulaSearchModule upgraded
Finished upgrade -

> Whoops, looks like something went wrong.

> 1/1ContextErrorException: Warning: session_regenerate_id(): Cannot regenerate session id - headers already sent in /Applications/MAMP/htdocs/135/vendor/symfony/symfony/src/Symfony/Component/HttpFoundation/Session/Storage/NativeSessionStorage.php line 209

> in /Applications/MAMP/htdocs/135/vendor/symfony/symfony/src/Symfony/Component/HttpFoundation/Session/Storage/NativeSessionStorage.php line 209
at ErrorHandler->handle('2', 'session_regenerate_id(): Cannot regenerate session id - headers already sent', '/Applications/MAMP/htdocs/135/vendor/symfony/symfony/src/Symfony/Component/HttpFoundation/Session/Storage/NativeSessionStorage.php', '209', array('destroy' => false, 'lifetime' => null))
at session_regenerate_id(false) in /Applications/MAMP/htdocs/135/vendor/symfony/symfony/src/Symfony/Component/HttpFoundation/Session/Storage/NativeSessionStorage.php line 209
at NativeSessionStorage->regenerate(false) in /Applications/MAMP/htdocs/135/lib/legacy/Zikula/Session/Storage/Legacy.php line 92
at Zikula_Session_Storage_Legacy->regenerate(false, null) in /Applications/MAMP/htdocs/135/vendor/symfony/symfony/src/Symfony/Component/HttpFoundation/Session/Session.php line 175
at Session->migrate() in /Applications/MAMP/htdocs/135/lib/legacy/Zikula/Session.php line 129
at Zikula_Session->regenerate(true) in /Applications/MAMP/htdocs/135/lib/legacy/util/SessionUtil.php line 54
at SessionUtil::setVar('uid', '2') in /Applications/MAMP/htdocs/135/lib/util/UserUtil.php line 926
at UserUtil::setUserByUid('2', false, array('modname' => 'ZikulaUsersModule', 'method' => 'uname')) in /Applications/MAMP/htdocs/135/lib/util/UserUtil.php line 844
at UserUtil::loginUsing(array('modname' => 'ZikulaUsersModule', 'method' => 'uname'), array('login_id' => 'craig', 'pass' => 'heyd8302')) in /Applications/MAMP/htdocs/135/upgrade.php line 301
at _upg_upgrademodules('craig', 'heyd8302') in /Applications/MAMP/htdocs/135/upgrade.php line 88