config: remove more obsolete or unneeded config options.

Remove more config options that were either unused or that shouldn't
need to be configured by downstream users.

app/models/post.rb

@@ -671,8 +671,6 @@ class Post < ApplicationRecord
     end
 
     def add_automatic_tags(tags)
-      return tags if !Danbooru.config.enable_dimension_autotagging
-
       tags -= %w(incredibly_absurdres absurdres highres lowres huge_filesize flash webm mp4)
 
       if has_dimensions?

app/models/post_appeal.rb

@@ -1,6 +1,8 @@
 class PostAppeal < ApplicationRecord
   class Error < Exception; end
 
+  MAX_APPEALS_PER_DAY = 1
+
   belongs_to :creator, :class_name => "User"
   belongs_to :post
   validates_presence_of :reason
@@ -47,8 +49,8 @@ class PostAppeal < ApplicationRecord
   end
 
   def validate_creator_is_not_limited
-    if appeal_count_for_creator >= Danbooru.config.max_appeals_per_day
-      errors[:creator] << "can appeal at most #{Danbooru.config.max_appeals_per_day} post a day"
+    if appeal_count_for_creator >= MAX_APPEALS_PER_DAY
+      errors[:creator] << "can appeal at most #{MAX_APPEALS_PER_DAY} post a day"
     end
   end
 

app/models/upload.rb

@@ -76,7 +76,7 @@ class Upload < ApplicationRecord
   def initialize_attributes
     self.uploader_id = CurrentUser.id
     self.uploader_ip_addr = CurrentUser.ip_addr
-    self.server = Danbooru.config.server_host
+    self.server = Socket.gethostname
   end
 
   def self.prune!(date = 1.day.ago)

app/models/user.rb

@@ -244,7 +244,8 @@ class User < ApplicationRecord
       end
 
       def sha1(pass)
-        Digest::SHA1.hexdigest("#{Danbooru.config.password_salt}--#{pass}--")
+        salt = "choujin-steiner"
+        Digest::SHA1.hexdigest("#{salt}--#{pass}--")
       end
     end
   end