fixes #20646 - clear host_id during interface cloning

(cherry picked from commit adbb8b53355314e1ee3bf0002ec6b224a911b31e)

Fixes #19742 - cache hosts for fact values

When we generate fact values hash we always loaded a host for a given
fact. This in combination with taxonomies queryies that are
automatically generated caused roughly 6N+1 issue. We can preload all
hosts that are required and use this in-memory cache for generating the...

Fixes #19400 - defer loading of tables list cache

The BookmarkControllerValidator can get loaded sooner than the tables
are loaded (especially in tests).

(cherry picked from commit f044c69d7d5ab83aa4d6787ece84ef7ba3fd06d5)

Conflicts:
app/validators/bookmark_controller_validator.rb

Fixes #19677 - Add settings for local boot templates

(cherry picked from commit 0e8f2cac4ed72ddf819582700977a4b6844a7c06)

fixes #18200 - don't re-encrypt settings when value is unchanged

Fixes #19266 - fix_db_cache crashes Rails initialization

The Filters cache that CacheManager recreates when
fix_db_cache is true, fails when the roles associated with said
filters are locked. To generate the cache, we call `.save` on the filter
object, which is not allowed by Role....

Fixes #19630 - ignore hidden admins

Fixes #19612 - CVE-2017-7505 don't expose admin to taxed users

(cherry picked from commit af9edf1098bf8e643e1607f9375595e375e7ade6)

Conflicts:
app/models/notification.rb

Fixes #19631 - ComputeResource with KeyPair can be removed

The concern for removing the compute resources with keypairs was trying
to destroy the compute resource too early. Also, this deletion already
happened because of the has_one :dependency => :destroy relation...

Fixes #19236 - handle situation when host is destroyed oVirt

The issue was introduced in 4269abbd, where we replaced the
`OVIRT::OvirtException` error by `ActiveRecord::RecordNotFound` in
`find_vm_by_uuid method`, but we haven't updated the corresponding...