[RFE] support multi nodes operations

so far, we just support multi node operations with 'ironic node-delete' command, in this blueprint, will cover more action to support multi node operations which should be easy for user to handle multi nodes with single commands.

And this is not BIG change, so think the spec is not required.

The list of commands which will be address in this bp:

node-get-boot-device
node-get-console
node-get-supported-boot-devices
node-set-boot-device
node-set-console-mode
node-set-maintenance
node-set-power-state
node-set-provision-state
node-show-states
node-update
node-validate
node-vendor-passthru

An example of node-set-power-state command changes:

Without this bp, current behavior:
ironic node-set-power-state <node> <power-state>

With this bp:
ironic node-set-power-state <node> [<node> ...] <power-state>

And also, the related osc-plugin code which is handing above commands for ironic client will be synced with these new option changes.