The messages now show where the request failed and what was
requested. This should help resolve both develper and end-user problems.
Also fixed the missing logging of the output string in the `parse`
callback of the main function and cleaned up the POSTed server body.
The test tests the internals of the cluster diff generation
algorithms. This should guarantee that the diff calculation and the
resulting synchronization will work as expected without having to test it
on a live cluster.
The `cluster sync` command synchronizes a MaxScale cluster with one
server. This allows new MaxScale instances to be synchronized with an old
instance by using the same configuration file and performing a cluster
sync.
The `cluster diff` command prints out the difference between the source
and target MaxScale. This allows users to detect changes that have
happened on one MaxScale but not on the other.
