Fixes #1483

The opera work around is still needed though! O_o

Standardized node.textContent is available since IE9

Our minimum PHP version requirement is now over 5.3, so this workaround is
not needed anymore. See also c9454ee3

reusing the diff colors as suggested by @selfthinker

restoring of mediafiles failed

missed a line in my last commit

This makes it easier to create tabs with an active tab (no need for
additional markup)

A few fixes.

we already do it for other passwords, so it makes sense to do it here as
well.

New Python Django application default to PBKDF2 with SHA256 as a
password mechanism. This adds support for that mechanism in our
password hasher class. This will be needed in the tests for the new
PDO auth plugin.

This makes sure the provided callback is using alphanumerics only. I'm
not sure this is needed, but better safe than sorry.

because we actually want it in this branch ;-)

This reverts commit 38a2174b.

this was an accidental commit to master

This reverts commit f7f7fb6c.

This introduces a mechanism to override what happens when a media item
is selected in the media manager popup by providing a callback name in
the URL. The default implementation just does what
dw_mediamanager.insert did before and calls insertTags()