Revert "admin: Rename virAdmConnect to virAdmDaemon"

Commmit df8192aa introduced admin related rename and some minor
(caused by automated approach, aka sed) and some more severe isues along with
it. First reason to revert is the inconsistency with libvirt library.
Although we deal with the daemon directly rather than with a specific
hypervisor, we still do have a connection. That being said, contributors might
get under the impression that AdmDaemonNew would spawn/start a new daemon
(since it's admin API, why not...), or AdmDaemonClose would do the exact
opposite or they might expect DaemonIsAlive report overall status of the daemon
which definitely isn't the case.
The second reason to revert this patch is renaming virt-admin client. The
client tool does not necessarily have to reflect the names of the API's it's
using in his internals. An example would be 's/vshAdmConnect/vshAdmDaemon'
where noone can be certain of what the latter function really does. The former
is quite expressive about some connection magic it performs, but the latter does
not say anything, especially when vshAdmReconnect and vshAdmDisconnect were
left untouched.

src/admin_protocol-structs

@@ -1,12 +1,12 @@
 /* -*- c -*- */
-struct admin_daemon_open_args {
+struct admin_connect_open_args {
         u_int                      flags;
 };
-struct admin_daemon_get_version_ret {
+struct admin_connect_get_lib_version_ret {
         uint64_t                   libVer;
 };
 enum admin_procedure {
-        ADMIN_PROC_DAEMON_OPEN = 1,
-        ADMIN_PROC_DAEMON_CLOSE = 2,
-        ADMIN_PROC_DAEMON_GET_VERSION = 3,
+        ADMIN_PROC_CONNECT_OPEN = 1,
+        ADMIN_PROC_CONNECT_CLOSE = 2,
+        ADMIN_PROC_CONNECT_GET_LIB_VERSION = 3,
 };