Fixes #21883 - improved user context switch logging

Fixes #22493 - structured logging support

Fixes #20957 - Replace alias_method_chain with Module prepend

Deprecated in Rails 5.0 and will be removed in 5.1. Some instances of
classes overwriting existing methods can be handled with `super`, other
concerns or modules are changed to use prepend instead of include....

Fixes #20248, #20327 - Respect context in CSV export

Since CSV export is done using an enumerator which is executed by a
different thread to the one that creates it, we need to manually pass in
the context (user, location, organization) to the enumerator.

fixes #19913 - fixes rubocop Style/ZeroLengthPredicate

Fixes #18949 - info message about current user

fixes #15720 - rename *_filter to *_action

The older 'filter' name is changing in Rails to 'action' and is being
deprecated.

Refs #3809 - Turning on some rubocop cops

Fixes #9657 - merge NICs from compute profile in host create API

- updated api docs for hosts and interfaces
- host create/update api actions now merge interfaces from compute
profiles
- NIC type mapping extracted into a separate class
- return full host detail after host update

Refs #3809 - Remove cops for empty lines