Added support for deleting files (the previous version only supported re...

Added support for deleting files (the previous version only supported removal of folders).

For the script to delete files instead of folders, the "f"-flag should be used when executing the script, e.g.:

./cleanup.sh -d /mnt/online-storage-01/dbbackups/prepared -t 10380 -f -v
(Will delete files older than 10380 minutes located in the "prepared"-folder.)

NOTE! When running the script using the "f"-flag only single files will be deleted. Folders will stay untouched.