Remove log level from options

Use standard setLogLevel and related methods for that.
Leave options object just for prefix-related options.

Author: LeartS

lib/log.js

@@ -31,12 +31,11 @@ const defaultTemplate = '[%t] %l [%n]:'
 // "Nice" default options, they make log lines like:
 // [2019-02-18T00:37:56.007] WARN [root]: This is a warning message
 // With colored log level, according to serverity.
-const defaultOptions = {
+const defaultLogLevelOptions = {
   levelFormatter: defaultLevelFormatter,
   timestampFormatter: defaultTimestampFormatter,
   nameFormatter: defaultNameFormatter,
   template: defaultTemplate,
-  level: 'WARN'
 }
 
 const _loggersByName = {}
@@ -50,7 +49,7 @@ const _loggersByName = {}
 class MonkLogger extends logLevel.constructor {
   constructor (name, level, options) {
     super(name, level)
-    this.options = {...defaultOptions}
+    this.options = {...defaultLogLevelOptions}
     this.configure(options)
   }
 
@@ -68,10 +67,9 @@ class MonkLogger extends logLevel.constructor {
    */
   configure (options, reset = false) {
     this.options = {
-      ...(reset ? defaultOptions : this.options),
+      ...(reset ? defaultLogLevelOptions : this.options),
       ...options,
     }
-    this.setLevel(this.options.level)
     prefix.apply(this, this.options)
   }