fixes #4245 - return HTTP body for oVirt SSL CA certificate

(cherry picked from commit 2e417b5824b4e5283586119052aed7b4953e468e)
fixes #4524 - The logged in user should be the default one in create new hosts

(cherry picked from commit 19579f872c1b4a512500f8e07f0b066180574e4e)
fixes #4485 prevents undefined method when cloning a host

(cherry picked from commit cdbbf1c231c9148d2b6ed252d920a8676c176702)
fixes #4442 - returning nil plays nice with try_to_login.

(cherry picked from commit a416bb573dedf6c34592afec17fbbec96691a5e6)
fixes #4194, #4459 - add main_app to root_path references for isolated engines

(cherry picked from commit 33b384f2b29363014608ac1b85061b5a8b4791d5)
fixes #4565 - puppet class free-text search is now significantly faster

(cherry picked from commit 0126385b4469accf2474ab3db0ef43f8d7b63558)
fixes #3475 - make it possible to force the 401 status.

(cherry picked from commit 5eb2fa6ec0997b31b95d413c64c6bc3b2cfe552e)