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.

store/store.go

@@ -6,8 +6,6 @@ package store
 import (
 	"time"
 
-	l4g "github.com/alecthomas/log4go"
-
 	"github.com/mattermost/mattermost-server/model"
 )
 
@@ -32,7 +30,7 @@ func Do(f func(result *StoreResult)) StoreChannel {
 func Must(sc StoreChannel) interface{} {
 	r := <-sc
 	if r.Err != nil {
-		l4g.Close()
+
 		time.Sleep(time.Second)
 		panic(r.Err)
 	}