Support missing parameters in vm.set for Vm updates

[ddelnano]

While #144 improved vm resource updates significantly (specifically #40 and #111), there are many parameters that are not supported with the vm resource. This issue tracks supporting all the vm.set parameters. This likely will require a breaking change with how memory is handled. Currently, the memory_max attribute modifies the static memory max on create and the dynamic memory max on updates. It might make sense to fix that as part of this change or that breaking change can be done in another issue.

[ddelnano]

Will #168 adds support for more parameters. Once that is merged the remaining parameters that need to be implemented will be the following:

• hasVendorDevice - must be applied when the vm is halted and only applies to windows machines
• virtualizationMod
• PV_args
• cpuMask
• cpuWeight
• cpuCap
• coresPerSocket
• share - I don't intend to implement this since it could be accomplished with the xenorchestra_resource_set resource
• secureBoot - this fails with the following validation error and I haven't been able to track down the cause

        Error: jsonrpc2: code 10 message: invalid parameters: {"errors":[{"code":null,"reason":"strict","message":"should not contains property [\"secureBoot\"]","property":"@"}]}