Add Force Update Button for VMs

[OscarMoya]

Some times a VM can be stalled, endlessly remaining on a transition status where the user (from Expedient) or the IM (from VMManager) can do nothing. The solution is to add a button allowing to retrieve synchronously the state of the VM in real time, updating VMManger and Expedient DB and apply the required actions, if any.

This feature adds a shortcut to update on the fly the VMs and avoid to wait until the BackgroundMonitoring notice something weird.

[OscarMoya]

Done.

An update button was added on the vt_pluguin slice template letting the users (Force)update a single VM a server or the whole AM in his slice.

Also, in VM Manager Manage servers template, the same button was added in order to update a single VM or the whole Server.

This action establishes a synchronous connection to the agent and changes the status of the VM Models.