[FOLLOWUP][TASK] Pagetrees: adopt open/close icons and align items of same level

Module Filelist -> Folder Tree: prevents the line break between icon and text.
Element Browser: Missing space between tree item text and .list-tree-show icon added.

Change-Id: I96907290dc49106b3a466fbd70656c51d61b4c39
Releases: master
Related: #68649
Reviewed-on: http://review.typo3.org/42232


Reviewed-by: Alexander Grein <mail@mediaessenz.de>
Tested-by: Alexander Grein <mail@mediaessenz.de>
Reviewed-by: Christian Kuhn <lolli@schwarzbu.ch>
Tested-by: Christian Kuhn <lolli@schwarzbu.ch>
Reviewed-by: Stefan Neufeind <typo3.neufeind@speedpartner.de>
Tested-by: Stefan Neufeind <typo3.neufeind@speedpartner.de>
Reviewed-by: Andreas Fernandez <typo3@scripting-base.de>
Tested-by: Andreas Fernandez <typo3@scripting-base.de>