CLOUDSTACK-7384: UI > Instances > detailView > change service offering option > hide it when VM state is Running and hyperviror is LXC.
CLOUDSTACK-7383: UI > Instances > detailView > snapshot option > hide this option when hypervisor is LXC.
CLOUDSTACK-7841: Gracefully reload haproxy config

The old way would disconnect all the existing connections through haproxy when
reload the config.

This new way would ensure that all the existing connections would still alive
after reload the config.