Do not escape HTML by default anymore (elastic#9914)

- export json encoder config object for initialization
- set escape_html default to false json formatter
- set escape_html default to false in ES, Console, LS outputs (other
  outputs require explicit formatter)
- Adapt reference configs
- Update docs

journalbeat.reference.yml

@@ -301,7 +301,7 @@ output.elasticsearch:
   #compression_level: 0
 
   # Configure escaping HTML symbols in strings.
-  #escape_html: true
+  #escape_html: false
 
   # Optional protocol and basic auth credentials.
   #protocol: "https"
@@ -408,7 +408,7 @@ output.elasticsearch:
   #compression_level: 3
 
   # Configure escaping HTML symbols in strings.
-  #escape_html: true
+  #escape_html: false
 
   # Optional maximum time to live for a connection to Logstash, after which the
   # connection will be re-established.  A value of `0s` (the default) will
@@ -545,7 +545,7 @@ output.elasticsearch:
     #pretty: false
 
     # Configure escaping HTML symbols in strings.
-    #escape_html: true
+    #escape_html: false
 
   # Metadata update configuration. Metadata contains leader information
   # used to decide which broker to use when publishing.
@@ -659,7 +659,7 @@ output.elasticsearch:
     #pretty: false
 
     # Configure escaping HTML symbols in strings.
-    #escape_html: true
+    #escape_html: false
 
   # The list of Redis servers to connect to. If load-balancing is enabled, the
   # events are distributed to the servers in the list. If one server becomes
@@ -779,7 +779,7 @@ output.elasticsearch:
     #pretty: false
 
     # Configure escaping HTML symbols in strings.
-    #escape_html: true
+    #escape_html: false
 
   # Path to the directory where to save the generated files. The option is
   # mandatory.
@@ -814,7 +814,7 @@ output.elasticsearch:
     #pretty: false
 
     # Configure escaping HTML symbols in strings.
-    #escape_html: true
+    #escape_html: false
 
 #================================= Paths ======================================