Implements a locking mechanism to prevent clobbering of node
flushes. When a flush begins, a global cluster lock is placed
which is freed once the flush completes. While the lock is in place,
other flush events queue waiting for the lock to free before
proceeding.
Modifies the CLI output flow when the `--wait` option is specified.
First, if a lock exists when running the command, the message is
tweaked to indicate this, and the client will wait first for the
lock to free, and then for the flush as normal. Second, the wait
depends on the active lock rather than the domain_status for
consistency purposes.
Closes#32
Completely restructure the daemon code to move the 4 discrete daemons
into a single daemon that can be run on every hypervisor. Introduce the
idea of a static list of "coordinator" nodes which are configured at
install time to run Zookeeper and FRR in router mode, and which are
allowed to take on client network management duties (gateway, DHCP, DNS,
etc.) while also allowing them to run VMs (i.e. no dedicated "router"
nodes required).
Joshua Boniface