Add pxe_loader to host REST

Add the field `pxe_loader` to the GET part of the hosts/
It is possible to set or update (POST, UPDATE), but not to read it

(cherry picked from commit b9f27ad9cb25862180793820eee5210cdc49ff75)

fixes #18574 - add ip6 address to the REST api results

(cherry picked from commit 71eb7ee0731726d41d76b839c56db0330e895187)

Fixes #17846 - auth_source_ldaps API now displays taxonomies

(cherry picked from commit 65c093a57f743567146012c3dfdae3653369218e)

Fixes #15232 - Showing inherited roles from User groups to user

Fixes #17153 - Consistent name for variable_type in the api

Fixes #17120 - Allow custom name for setting category

Fixes #17107 - list override in filter API

fixes #16725 - add plugin extension point for smart proxies

Fixes #14277 - Added description field to users

Fixes #16114 - Expose host parameters to GET /api/hosts