Switch default level to INFO

This is part of elastic#1931 and fixes elastic#1734.

Some things to note/discuss:

* `-v` does nothing by default now. However, it's possible that you
set it to error in the config file and then use -v to go back to
info level at the CLI. So I kept the option.
* the `logging.level: debug` from the default configuration also
doesn nothing now, unless you also specify some selectors. So I added
also a `logging.selectors: ["*"]` to the default short config.
* While not all of elastic#1931 is done yet, I think we can proceed with the
default level change to fix elastic#1734 and then we do more INFO/WARN cleanups
in future PRs.

filebeat/filebeat.full.yml

@@ -686,7 +686,7 @@ output.elasticsearch:
 #logging.level: error
 
 # Enable debug output for selected components. To enable all selectors use ["*"]
-# Other available selectors are beat, publish, service
+# Other available selectors are "beat", "publish", "service"
 # Multiple selectors can be chained.
 #logging.selectors: [ ]
 

filebeat/filebeat.yml

@@ -111,3 +111,8 @@ output.elasticsearch:
 # Sets log level. The default log level is error.
 # Available log levels are: critical, error, warning, info, debug
 #logging.level: debug
+
+# At debug level, you can selectively enable logging only for some components.
+# To enable all selectors use ["*"]. Examples of other selectors are "beat",
+# "publish", "service".
+#logging.selectors: ["*"]

libbeat/_meta/config.full.yml

@@ -472,7 +472,7 @@ output.elasticsearch:
 #logging.level: error
 
 # Enable debug output for selected components. To enable all selectors use ["*"]
-# Other available selectors are beat, publish, service
+# Other available selectors are "beat", "publish", "service"
 # Multiple selectors can be chained.
 #logging.selectors: [ ]
 

libbeat/_meta/config.yml

@@ -53,3 +53,8 @@ output.elasticsearch:
 # Sets log level. The default log level is error.
 # Available log levels are: critical, error, warning, info, debug
 #logging.level: debug
+
+# At debug level, you can selectively enable logging only for some components.
+# To enable all selectors use ["*"]. Examples of other selectors are "beat",
+# "publish", "service".
+#logging.selectors: ["*"]

libbeat/logp/logp.go

@@ -124,7 +124,7 @@ func SetStderr() {
 
 func getLogLevel(config *Logging) (Priority, error) {
 	if config == nil || config.Level == "" {
-		return LOG_ERR, nil
+		return LOG_INFO, nil
 	}
 
 	levels := map[string]Priority{

metricbeat/metricbeat.full.yml

@@ -617,7 +617,7 @@ output.elasticsearch:
 #logging.level: error
 
 # Enable debug output for selected components. To enable all selectors use ["*"]
-# Other available selectors are beat, publish, service
+# Other available selectors are "beat", "publish", "service"
 # Multiple selectors can be chained.
 #logging.selectors: [ ]
 

metricbeat/metricbeat.yml

@@ -99,3 +99,8 @@ output.elasticsearch:
 # Sets log level. The default log level is error.
 # Available log levels are: critical, error, warning, info, debug
 #logging.level: debug
+
+# At debug level, you can selectively enable logging only for some components.
+# To enable all selectors use ["*"]. Examples of other selectors are "beat",
+# "publish", "service".
+#logging.selectors: ["*"]

packetbeat/packetbeat.full.yml

@@ -856,7 +856,7 @@ output.elasticsearch:
 #logging.level: error
 
 # Enable debug output for selected components. To enable all selectors use ["*"]
-# Other available selectors are beat, publish, service
+# Other available selectors are "beat", "publish", "service"
 # Multiple selectors can be chained.
 #logging.selectors: [ ]
 

packetbeat/packetbeat.yml

@@ -142,3 +142,8 @@ output.elasticsearch:
 # Sets log level. The default log level is error.
 # Available log levels are: critical, error, warning, info, debug
 #logging.level: debug
+
+# At debug level, you can selectively enable logging only for some components.
+# To enable all selectors use ["*"]. Examples of other selectors are "beat",
+# "publish", "service".
+#logging.selectors: ["*"]

winlogbeat/winlogbeat.full.yml

@@ -507,7 +507,7 @@ output.elasticsearch:
 #logging.level: error
 
 # Enable debug output for selected components. To enable all selectors use ["*"]
-# Other available selectors are beat, publish, service
+# Other available selectors are "beat", "publish", "service"
 # Multiple selectors can be chained.
 #logging.selectors: [ ]
 

winlogbeat/winlogbeat.yml

@@ -77,3 +77,8 @@ output.elasticsearch:
 # Sets log level. The default log level is error.
 # Available log levels are: critical, error, warning, info, debug
 #logging.level: debug
+
+# At debug level, you can selectively enable logging only for some components.
+# To enable all selectors use ["*"]. Examples of other selectors are "beat",
+# "publish", "service".
+#logging.selectors: ["*"]