Unirec output: add HTTP user agent and remove HTTP Method ID to Method Mask

The user agent is required by V. Bartos and the mask is proper field
identification used by Flowmon Exporter configuration.

Author: Lukas955

extra_plugins/output/unirec/config/unirec-elements.txt

@@ -127,7 +127,6 @@ HTTP_REQUEST_REFERER           string        e16982id505
 HTTP_RESPONSE_STATUS_CODE      uint32        e16982id506                        # HTTP response status code
 HTTP_RESPONSE_CONTENT_TYPE     string        e16982id507                        # HTTP response content type
 
-FME_HTTP_METHOD_ID             uint16        flowmon:httpMethodID
 FME_HTTP_UA_OS                 uint16        flowmon:httpUaOs
 FME_HTTP_UA_OS_MAJ             uint16        flowmon:httpUaOsMaj
 FME_HTTP_UA_OS_MIN             uint16        flowmon:httpUaOsMin
@@ -136,9 +135,11 @@ FME_HTTP_UA_APP                uint16        flowmon:httpUaApp
 FME_HTTP_UA_APP_MAJ            uint16        flowmon:httpUaAppMaj
 FME_HTTP_UA_APP_MIN            uint16        flowmon:httpUaAppMin
 FME_HTTP_UA_APP_BLD            uint16        flowmon:httpUaAppBld
+FME_HTTP_METHOD_MASK           uint16        flowmon:httpMethodMask
 FME_HTTP_REQUEST_HOST          string        flowmon:httpHost                   # HTTP(S) request host
 FME_HTTP_REQUEST_URL           string        flowmon:httpUrl                    # HTTP request url
 FME_HTTP_RESPONSE_STATUS_CODE  uint32        flowmon:httpStatusCode             # HTTP response status code
+FME_HTTP_REQUEST_USER_AGENT    string        flowmon:httpUserAgent
 
 # --- Other fields ---
 IPV6_TUN_TYPE                  uint8         e16982id405                        # IPv6 tunnel type