def prepend_befores(commands, befores = nil)
      unless befores.nil? || befores.empty?
        commands.insert(0, befores).flatten!
      else
        commands
      end
    end
def prepend_befores(commands, befores = nil)
      unless befores.nil? || befores.empty?
        commands.insert(0, befores).flatten!
      else
        commands
      end
    end
Prepends the :before commands to the current context's
 commands if it exists.

 @param [Array<String>] commands
   The current tab commands
 @param [Array<String>] befores
   The current window's :befores

 @return [Array<String>]
   The current context commands with the :before commands prepended

 @api public