🐛 Fixed log file rotation

closes #60

- was introduced in #59
- the initial fix of PR #59 was the correct fix
- `rotate-file` type is a real file stream (!)
- we should only register this stream type if rotation is enabled, because
  - type `file` always writes into the oldest log file
  - type `rotate-file` writes into the latest log file
- because we had ignored rotate streams for logging, which we thought is the right solution, the `file` stream has written into the oldest log file and this ended up in a huge log file after a couple of days (depends on the load)

lib/logging/GhostLogger.js

@@ -142,30 +142,6 @@ class GhostLogger {
             return;
         }
 
-        this.streams['file-errors'] = {
-            name: 'file',
-            log: bunyan.createLogger({
-                name: 'Log',
-                streams: [{
-                    path: `${this.path}${sanitizedDomain}_${this.env}.error.log`,
-                    level: 'error'
-                }],
-                serializers: this.serializers
-            })
-        };
-
-        this.streams['file-all'] = {
-            name: 'file',
-            log: bunyan.createLogger({
-                name: 'Log',
-                streams: [{
-                    path: `${this.path}${sanitizedDomain}_${this.env}.log`,
-                    level: this.level
-                }],
-                serializers: this.serializers
-            })
-        };
-
         if (this.rotation.enabled) {
             this.streams['rotation-errors'] = {
                 name: 'rotation-errors',
@@ -196,6 +172,30 @@ class GhostLogger {
                     serializers: this.serializers
                 })
             };
+        } else {
+            this.streams['file-errors'] = {
+                name: 'file',
+                log: bunyan.createLogger({
+                    name: 'Log',
+                    streams: [{
+                        path: `${this.path}${sanitizedDomain}_${this.env}.error.log`,
+                        level: 'error'
+                    }],
+                    serializers: this.serializers
+                })
+            };
+
+            this.streams['file-all'] = {
+                name: 'file',
+                log: bunyan.createLogger({
+                    name: 'Log',
+                    streams: [{
+                        path: `${this.path}${sanitizedDomain}_${this.env}.log`,
+                        level: this.level
+                    }],
+                    serializers: this.serializers
+                })
+            };
         }
     }
 
@@ -306,9 +306,6 @@ class GhostLogger {
             // because it would result in duplicate logs
             if (type === 'error' && logger.name === 'stdout' && includes(this.transports, 'stderr')) {
                 return;
-            } else if ( logger.name.indexOf('rotation') > -1 ) {
-                // https://github.com/TryGhost/Ignition/pull/59
-                return;
             }
 
             /**