removed has_many_polymorphs and used has_many :source and :source_type

fixes #2062 - Add max_trends setting

Do not use :class_name in has_many :through, missed on for class_params

removed class_name from all relationships that has_many :through as its invalid.

It seems like we hit a rails bug, where the joins were incorrectly created,
once removed, it was generated correctly.

reviewing the docs again, say that its ignored with hmt relation, so removing anyway.

fixes #1834 to get foreman running under ruby 1.9.3

added slash /unattended to other url_for calls

fixes #2023 - Don't try to save os=nil in the fact importer

I've tried to address all possible places where empty set of facts (e.g. we
dont have the facts just yet as its a brand new install) could lead to the
operating system value disappering.

i believe the issue happened because of a boolean == string compareing (e.g....

Fix Foreman SQL injection through search mechanism CVE-2012-5648

fixes #1978 - changing login maximum size to 100

In case of using a long login name (such as ovirt_username@domain), on
the fly login will fail. Increasing the maximum login size to 100.

fixes #2045 changed condition so there is no error in Postgresql