MB-5307:refactored ns_port_init to avoid excessive recomputations
MB-5307:refactored ns_port_init to avoid excessive recomputations

Previously it considered any ns_config event as potential change of
port servers config. That's obvious waste of CPU.

New code only ignores irrelevant events and also avoids talking to
supervisor unless reconfiguration is really needed.

Change-Id: Ia1c348ea59837c4742ea389b17f99e81a871c408
Reviewed-on: http://review.couchbase.org/16776
Tested-by: Aliaksey Kandratsenka <340b8e09ca65cd3fc686427fcfed17e87eaf61e2@gmail.com>
Reviewed-by: Aliaksey Artamonau <3c875bcfb3adf2a65b2ae7686ca921e6c9433147@gmail.com>

daverigby/ns_server,mschoch/ns_server,ceejatec/ns_server,daverigby/ns_server,pavel-blagodov/ns_server,pavel-blagodov/ns_server,ceejatec/ns_server,nimishzynga/ns_server,t3rm1n4l/ns_server,vzasade/ns_server,daverigby/ns_server,membase/ns_server,t3rm1n4l/ns_server,ceejatec/ns_server,nimishzynga/ns_server,mschoch/ns_server,ceejatec/ns_server,membase/ns_server,t3rm1n4l/ns_server,vzasade/ns_server,mschoch/ns_server,nimishzynga/ns_server,ceejatec/ns_server,t3rm1n4l/ns_server,mschoch/ns_server,pavel-blagodov/ns_server,ceejatec/ns_server,nimishzynga/ns_server,vzasade/ns_server,mschoch/ns_server,nimishzynga/ns_server,membase/ns_server,pavel-blagodov/ns_server,daverigby/ns_server,membase/ns_server,t3rm1n4l/ns_server,mschoch/ns_server,vzasade/ns_server,membase/ns_server,nimishzynga/ns_server,membase/ns_server,daverigby/ns_server