[BUGFIX] Resource storage does not emit signals

The ResourceStorage class should emit signals before and after most
actions it performs. The emit*() methods are already there, but not
called from the "action" methods. This commit adds the calls where
missing.

Change-Id: Icf1653975aa72762ab61c6d649207c5900e66b1d
Resolves: #46587
Releases: 6.1, 6.0
Reviewed-on: https://review.typo3.org/19221
Reviewed-by: Alexander Opitz
Reviewed-by: Wouter Wolters
Reviewed-by: Tom Ruether
Reviewed-by: Benjamin Mack
Tested-by: Benjamin Mack