Replace all rlog occurrences with the shared logger (#350)

* Replace all `rlog` occurrences with the shared logger

* Use the same log format in `InitLoggerStderrOnly` as well

* Convert one more `log.Fatal` to `logger.Log.Errorf` as well in the `cli`

* Replace `log.` occurrences with `logger.Log.` in `agent`

* Fix `cannot use err (type error)`

* Change the logging level to `DEBUG`

* Replace an `Errorf` with `Fatal`

* Add informative message

agent/pkg/rules/rulesHTTP.go

@@ -8,7 +8,7 @@ import (
 	"regexp"
 	"strings"
 
-	"github.com/romana/rlog"
+	"github.com/up9inc/mizu/shared/logger"
 
 	"github.com/google/martian/har"
 	"github.com/up9inc/mizu/shared"
@@ -69,7 +69,7 @@ func MatchRequestPolicy(harEntry har.Entry, service string) (resultPolicyToSend
 				if err != nil {
 					continue
 				}
-				rlog.Info(matchValue, rule.Value)
+				logger.Log.Info(matchValue, rule.Value)
 			} else {
 				val := fmt.Sprint(out)
 				matchValue, err = regexp.MatchString(rule.Value, val)