UI: reservation view: wizard for making a reservation

[danbim]

The wizard would help a user to make a reservation based on his personal requirements. It would e.g., ask the user for the set of required nodes (e.g. using a table-based selection that can be filtered based on several criteria). Then it would e.g. find the next free time slot(s) of the required size at which the testbed would be available for the reservation and propose these to the user for selection.