This commit provides a simple contract that if the BackupItemAction
plugin sets an annotation in a resource it has handled, the additional
items will considered "must include" i.e. each of them will skip the
"include-exclude" filter, such that the plugin developer can make sure
they are included in the backup disregarding the filter setting in the
bakcup CR.
Signed-off-by: Daniel Jiang <jiangd@vmware.com>