Update core/model/modx/sources/modfilemediasource.class.php

See http://tracker.modx.com/issues/8392

The base_url should not be prefixed when you setup a media source relative
added contains/containsnot conditional

It seems not to be possible to write own conditonal modifiers as snippet, so I would like to add them to the core.
Added method for clearing cache of resource

I think it is vary useful method, that is need for many developers.
I use it in my component and can do just
<pre>$res = $modx->getObject('modResource', 15);
$res->clearCache();
</pre>
Fix same categories on other parent levels. See tracker issue #9052
[#9129] Add refreshURIs call as part of clearing the site cache
Adding event to the middle mouse button click.

This is a continuation of https://github.com/modxcms/revolution/pull/449 in another realization. 
And prevent changes in the current window
Merge remote-tracking branch 'xpdo/develop' into develop

* xpdo/develop:
  [#9629] Fix notice in xPDOConnection::getOption() when $options not an array
  [#9020] Prevent xPDOZip from attempting to add empty targets
Merge remote-tracking branch 'xpdo/develop' into develop

* xpdo/develop:
  Bump version for xPDO 2.2.6-pl release
  [#7452] Fix sql errors with decimal fields in some locales
  [#9062] Fix problem loading multiple xPDOQuery driver classes
Added soft remove processor
Merge remote-tracking branch 'xpdo/develop' into develop
Merge remote-tracking branch 'xpdo/develop' into develop
Merge remote-tracking branch 'xpdo/develop' into develop

* xpdo/develop:
  Various documentation corrections
  Fix xPDOIterator->next() using void return value
  Fix undefined constant object in xPDO->toCache()
  Fix xPDO::prepare() sending no driver_options
  Fix xPDO::getInstance() when reusing existing
  Fix invalid call to $this->xpdo->log()
  [#9864] Identify compound PK's properly in xPDOQuery::parseConditions()
  Bump version for 2.2.8-dev
  Update getPK() to look for Schema Version 1.1 indexes first
  Check ob_get_level() at ob_end_* calls where ob wasn't explicitly started
Merge remote-tracking branch 'xpdo/develop' into develop

* xpdo/develop:
  Bump version for 2.2.8-pl release
Error property added plus getter and checker for it
modError is instantiated when sending fails
Error getter renamed
Merge remote-tracking branch 'xpdo/develop' into develop

* xpdo/develop:
  Fix xPDOTest::getTableMeta() error (sqlite/sqlsrv)
  Bump version for 2.2.9-dev
  Wrong query statistic counting
  [#10183] Fix cache entry removal on xPDOObject::remove()
xPDO 2.2.9-pl

Merge remote-tracking branch 'xpdo/develop' into develop

* xpdo/develop:
  Bump version for 2.2.9-pl release
Fix unescaped backslash in file and image TV

Fix for #9526: http://tracker.modx.com/issues/9526