Remove the Database module

Author: kddnewton

lib/syntax_tree.rb

@@ -21,7 +21,6 @@ module SyntaxTree
   # CLI. Requiring those features takes time, so we autoload as many constants
   # as possible in order to keep the CLI as fast as possible.
 
-  autoload :Database, "syntax_tree/database"
   autoload :DSL, "syntax_tree/dsl"
   autoload :FieldVisitor, "syntax_tree/field_visitor"
   autoload :Index, "syntax_tree/index"