cleanups to rails 3 boot process

code smell

fixes #1530 - Disabling puppet env in ENC is now a configurable.

fixes #1528 - tidy up the default settings loader.

Attempts to tidy up the default settings a bit.

Signed-off-by: Mikael Fridh <frimik@gmail.com>

fixes #1446 - expire idle web sessions

fixes #1300 Add support of HTTP Auth with REMOTE_USER env variable

WIP rails3 migration

Fixes #636 - Update environment from facts

Signed-off-by: Paul Kelly <paul.ian.kelly@googlemail.com>

wrong setting category - refs #636

fixes #685 - records per page should be configurable

This patch adds a new setting how many records should be per page.

note that since the code is in the ActiveRecord::Base class, and that
its in lib (e.g. loaded once) you would need to restart foreman everytime you change this value....