Structured logging (#8673)

* Implementing structured logging

* Changes to en.json to allow refactor to run.

* Fixing global logger

* Structured logger initalization.

* Add caller.

* Do some log redirection.

* Auto refactor

* Cleaning up l4g reference and removing dependancy.

* Removing junk.

* Copyright headers.

* Fixing tests

* Revert "Changes to en.json to allow refactor to run."

This reverts commit fd8249e99bcad0231e6ea65cd77c32aae9a54026.

* Fixing some auto refactor strangeness and typo.

* Making keys more human readable.

app/plugin/ldapextras/plugin.go

@@ -8,10 +8,10 @@ import (
 	"net/http"
 	"sync/atomic"
 
-	l4g "github.com/alecthomas/log4go"
 	"github.com/gorilla/mux"
 
 	"github.com/mattermost/mattermost-server/app/plugin"
+	"github.com/mattermost/mattermost-server/mlog"
 	"github.com/mattermost/mattermost-server/model"
 )
 
@@ -34,7 +34,7 @@ func (p *Plugin) config() *Configuration {
 func (p *Plugin) OnConfigurationChange() {
 	var configuration Configuration
 	if err := p.api.LoadPluginConfiguration(&configuration); err != nil {
-		l4g.Error(err.Error())
+		mlog.Error(err.Error())
 	}
 	p.configuration.Store(&configuration)
 }