Fixes #9615 - Adds inheriting_mac method

Using this method we can find out the MAC of interface to which this
interface is attached to. This can be used in provisioning template when
we check for real interface name.

(cherry picked from commit 5ad3c4f34b50fb1ac6d9f26e71e183813ab1c96f)

fixes #8878 - ensure domain fact is downcased prior to import

(cherry picked from commit 25a647eb04ac2d31af99c85e447d58d1de4185e6)

Fixes #9547 - DHCP is default subnet boot mode

(cherry picked from commit 9e5fad812a64055272b9cc650c2d387027638c71)

Fixes #9590 - make info test less fragile

(cherry picked from commit e24c3fbbe5d089f76b89f909b65b2bd2205a5035)

Refs #9500 - revert normalize_name tests

Current test "#normalize_hostname sets a domain based on name that contains its name if it's nil and such domain exists" is not testing anything because Domain.all does not return any domains to match (as .create was substituted on merge by .build)....

Fixes #9495 - Require identifier for managed bonds

(cherry picked from commit e329155b185e3be5863bfd79582b61a6ecc9ae9a)

Fixes #9497 - Require MAC for managed BMC

(cherry picked from commit 6a2fce1fa6a80865bb8292e76a8bd285e714a5c8)

Fixes #9427 - Return meaningful errors from subnets/freeip and parse the error response to the UI

(cherry picked from commit b9521a8dc7f4e61a011cabbfdfe78657bd3c24d2)

Fixes #9147 - move managed checks to the start of the DHCP/DNS/TFTP orchestration checks

(cherry picked from commit 5440d482b0087fe29b3fb4567e0ca73f2d3af221)

fixes #8331 - provide some tools for filtering mail

(cherry picked from commit a08e66ff1192e00d6dd8eafccd5bf5cd0e4183f9)