parser: use safer mechanism for allowing URLs

parser: use safer mechanism for allowing URLs

Having a default-remove boolean flag is making it easier to get this
right and decouple the if-branches that check if something is OK
(which may get more complex in the future) from the actual handling of
the result by always removing the href attribute if not explicitly
told otherwise.

Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com>