analyzer: fix for unregistering client
analyzer: fix for unregistering client

Prevent WebUI and others client (that are not Analyzers) to remove graph
that were not added by them.

Example: WebUI is analyzer's WSClient, so each time reload occurs it will
cause OnUnregisterClient(), but the code executed is relevant only for
Agent clients, so after browser page refresh, Fabric nodes are not exists
anymore.

Change-Id: I31aa7953a111035c1c540bc87685693570a34480
Signed-off-by: Konstantin Dorfman <123db30ff0b691a58cf0ff9819721ec6c3581334@il.ibm.com>
Signed-off-by: Eran Raichstein <df481ed6298ccb0a050ff711dbc815f26e1b9160@il.ibm.com>
Reviewed-on: https://softwarefactory-project.io/r/6478
Reviewed-by: Sylvain Baubeau <b0a7dc08a3f38d713e107103b0a85b0badc14b84@redhat.com>
Tested-by: Sylvain Baubeau <b0a7dc08a3f38d713e107103b0a85b0badc14b84@redhat.com>
Workflow: Sylvain Baubeau <b0a7dc08a3f38d713e107103b0a85b0badc14b84@redhat.com>

lebauce/skydive,safchain/skydive,redhat-cip/skydive,safchain/skydive,skydive-project/skydive,skydive-project/skydive,safchain/skydive,skydive-project/skydive,lebauce/skydive,lebauce/skydive,lebauce/skydive,redhat-cip/skydive,safchain/skydive,lebauce/skydive,skydive-project/skydive,safchain/skydive,skydive-project/skydive,lebauce/skydive,safchain/skydive,skydive-project/skydive,lebauce/skydive,safchain/skydive,redhat-cip/skydive,lebauce/skydive,safchain/skydive,skydive-project/skydive