CRAFTERCMS-214
Adding more log statements
Merge remote-tracking branch 'origin/CRAFTERCMS-214'
CRAFTERCMS-227: Delete should not be available when a content is locked

When a content is locked, the 'Delete' option is not available neither
in the contextual navigation nor in the "right-click" menu. Also, in
the case of bulk operations, if at least one content is locked within
all selected then the "Delete" option is not available either.