When the rbd-driver starts, it initializes some global (yuck!) variables
in the rbd package. Because the rbd-driver is moved out into its own
package, these variables can not easily be set anymore.
Introcude SetGlobalInt(), SetGlobalBool() and InitJournals() so that the
rbd-driver can configure the rbd package.
Signed-off-by: Niels de Vos <ndevos@redhat.com>