Handle IPv6 zone id in IIS filebeat ingest pipeline (elastic#9869)

IIS logs can include zone ids when using IPv6, this is correctly parsed
but geoip processor doesn't accept these addresses. Create a temporary
field without the zone id to be used by geoip processor.

CHANGELOG.next.asciidoc

@@ -54,6 +54,7 @@ https://github.com/elastic/beats/compare/v7.0.0-alpha2...master[Check the HEAD d
 *Filebeat*
 
 - Add `convert_timezone` option to Elasticsearch module to convert dates to UTC. {issue}9756[9756] {pull}9761[9761]
+- Support IPv6 addresses with zone id in IIS ingest pipeline. {issue}9836[9836] {pull}9869[9869]
 
 *Heartbeat*
 

filebeat/module/iis/error/ingest/default.json

@@ -28,10 +28,24 @@
       "field": "iis.error.time"
     }
   }, {
-    "geoip": {
+    "grok": {
       "field": "iis.error.remote_ip",
+      "patterns": [
+        "%{NOZONEIP:iis.error.remote_ip_geoip}"
+      ],
+      "pattern_definitions": {
+         "NOZONEIP": "[^%]*"
+      }
+    }
+  }, {
+    "geoip": {
+      "field": "iis.error.remote_ip_geoip",
       "target_field": "iis.error.geoip"
     }
+  }, {
+    "remove": {
+      "field": "iis.error.remote_ip_geoip"
+    }
   }],
   "on_failure" : [{
     "set" : {

filebeat/module/iis/error/test/ipv6_zone_id.log

@@ -0,0 +1,5 @@
+#Software: Microsoft HTTP API 2.0
+#Version: 1.0
+#Date: 2018-12-30 13:48:36
+#Fields: date time c-ip c-port s-ip s-port cs-version cs-method cs-uri streamid sc-status s-siteid s-reason s-queuename
+2018-12-30 14:22:07 ::1%0 49958 ::1%0 80 - - - - - - Timer_ConnectionIdle -

filebeat/module/iis/error/test/ipv6_zone_id.log-expected.json

@@ -0,0 +1,16 @@
+[
+    {
+        "@timestamp": "2018-12-30T14:22:07.000Z",
+        "ecs.version": "1.0.0-beta2",
+        "event.dataset": "error",
+        "event.module": "iis",
+        "iis.error.queue_name": "-",
+        "iis.error.reason_phrase": "Timer_ConnectionIdle",
+        "iis.error.remote_ip": "::1%0",
+        "iis.error.remote_port": "49958",
+        "iis.error.server_ip": "::1%0",
+        "iis.error.server_port": "80",
+        "input.type": "log",
+        "log.offset": 195
+    }
+]