MB-8855 Lower xdcrMaxConcurrentReps limit.
MB-8855 Lower xdcrMaxConcurrentReps limit.

Change-Id: I6e0dd0e5327e67c01de132be5667139546b0deec
Reviewed-on: http://review.couchbase.org/28316
Reviewed-by: Aliaksey Kandratsenka <340b8e09ca65cd3fc686427fcfed17e87eaf61e2@gmail.com>
Reviewed-by: Junyi Xie <cec9b1c9f34a8d92cba938f3f3364d5120580782@gmail.com>
Tested-by: Aliaksey Artamonau <3c875bcfb3adf2a65b2ae7686ca921e6c9433147@gmail.com>

ceejatec/ns_server,t3rm1n4l/ns_server,nimishzynga/ns_server,membase/ns_server,mschoch/ns_server,nimishzynga/ns_server,mschoch/ns_server,membase/ns_server,nimishzynga/ns_server,daverigby/ns_server,membase/ns_server,ceejatec/ns_server,mschoch/ns_server,membase/ns_server,daverigby/ns_server,daverigby/ns_server,membase/ns_server,mschoch/ns_server,nimishzynga/ns_server,mschoch/ns_server,t3rm1n4l/ns_server,ceejatec/ns_server,ceejatec/ns_server,t3rm1n4l/ns_server,membase/ns_server,t3rm1n4l/ns_server,ceejatec/ns_server,nimishzynga/ns_server,vzasade/ns_server,t3rm1n4l/ns_server,mschoch/ns_server,nimishzynga/ns_server,daverigby/ns_server,ceejatec/ns_server,vzasade/ns_server,daverigby/ns_server,vzasade/ns_server,vzasade/ns_server