Remove a few Scratch db features

Author: rgantzos

features/features.json

@@ -124,11 +124,6 @@
     "id": "better-trending-thumbnails",
     "versionAdded": "v3.4.0"
   },
-  {
-    "version": 2,
-    "id": "relevant-forum-posts",
-    "versionAdded": "v3.4.0"
-  },
   {
     "version": 2,
     "id": "anti-generic",
@@ -264,11 +259,6 @@
     "id": "shared-clipboard",
     "versionAdded": "v3.0.0"
   },
-  {
-    "version": 2,
-    "id": "important-messages",
-    "versionAdded": "v3.0.0"
-  },
   {
     "version": 2,
     "id": "hide-footer",
@@ -467,15 +457,6 @@
     "tags": ["New"],
     "type": ["Website"]
   },
-  {
-    "title": "Show User Statistics",
-    "description": "Replaces the 'What I've been doing' section on a profile page with the user's statistics.",
-    "credits": ["Dr_Lego"],
-    "urls": ["https://scratch.mit.edu/users/Dr_Lego/"],
-    "file": "user-stats",
-    "type": ["Website"],
-    "tags": ["New"]
-  },
   {
     "title": "Frontpage Curator Name as Link",
     "description": "Makes the name of the Frontpage Curator to a clickable link to his profile.",