More jruby gem for database fixes master

Improving PostgreSQL adapter schema-awareness

rake assets:clean also removes directories

See https://github.com/rails/rails/pull/1776#issuecomment-1402894,
2df2bfdb, and
7440a254.

Use uglifier from rubygems instead of git repo

This group is required by default only on development and test
(you can change it on config/application.rb).

`rake assets:precompile` will automatically add the assets group
to Rails.groups (and consequently Bundler.require) and should work
transparently.

Fix regexp in generators for right catching error message

Merge pull request #1787 from cmeiklejohn/make_fragment_for_more_robust_for_subclasses_of_safe_buffer

fragment_for assumes ActionView::OutputBuffer.

Do not change a frozen text passed to simple_format text helper 

Removing shadowing outer local variables warnings

Add missing require 'set'

assets:clean task now cleans up images

Removing require_relative gem. Linecache new version 0.46 is out and it's

Removing require_relative gem. Linecache new version 0.46 is out and it's loading rbx-require-relative > 0.0.4

Fix default options argument on ActiveRecord::ConnectionAdaptors::Table#column_exists?