With the permission of Romain Degez, CTO of Smartjog.

Signed-off-by: Sébastien Luttringer <sebastien.luttringer@smartjog.com>

otherwise log to syslog

Moved some parts to cc-common
Added logging handler for cc-common
Modified binary

Clean authentication code.

Harmless renaming.

New class RootDB has no parents and handles RPC calls to the cc-server in a
transparent fashion from its children.

JobManager + BaseJob.

When role changes in a new authentication attempt.
Was missing a method on MainLoop instance to unregister all plugins.

Tag version was not registered.

Set rpc_con to False in restart_rpc_connection.

When doing remote execution, it was sometimes failing with the following
exception: OSError: [Errno 10] No child processes.
The problem is when using libev default loop, the latest register a handler for
SIGCHLD, it causes a problem when Popen.communicate() tried to do a wait_pid,
the syscall is skipped because of the signal. Then when wait_pid is called
again, it failed because the process don't exist anymore.

When the node is disconnected from the cc-server, it keeps it internal state
until the connection pass, then in case the same role is returned by the
cc-server, it just reregister its objects and tags, else it remove the previous
main plugin and recreate a new one corresponding to the adequate role.

Support for registering/unregistering sub object to the cc-server.
Support for tag lifecycle handling (libev), was previously managed by plugins.

Plus error handling.

Refactored plugins.
Updated hypervisor libvirt event handling.
Async rpc handling.
Minor renaming for libvirt event callback.
Remove uneeded method sub_tags (in hypervisor Handler).