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.

einterfaces/brand.go

@@ -4,8 +4,9 @@
 package einterfaces
 
 import (
-	"github.com/mattermost/mattermost-server/model"
 	"mime/multipart"
+
+	"github.com/mattermost/mattermost-server/model"
 )
 
 type BrandInterface interface {

einterfaces/oauthproviders.go

@@ -4,8 +4,9 @@
 package einterfaces
 
 import (
-	"github.com/mattermost/mattermost-server/model"
 	"io"
+
+	"github.com/mattermost/mattermost-server/model"
 )
 
 type OauthProvider interface {