update changelog for 1.0.0-rc3 release
update changelog for 1.0.0-rc3 release

yosiat/kapacitor,adityacs/kapacitor,muxinc/kapacitor,adityacs/kapacitor,yosiat/kapacitor,titilambert/kapacitor,sputnik13/kapacitor,titilambert/kapacitor,influxdata/kapacitor,sputnik13/kapacitor,muxinc/kapacitor,influxdata/kapacitor,yosiat/kapacitor,influxdb/kapacitor,bbczeuz/kapacitor,adityacs/kapacitor,sputnik13/kapacitor,influxdata/kapacitor,titilambert/kapacitor,bbczeuz/kapacitor,muxinc/kapacitor,influxdb/kapacitor,bbczeuz/kapacitor,influxdb/kapacitor