Raise server/client timeouts to 3h (bnc#897902)

the 50s was generally by far too low, as it interrupts
api operations that take longer than that to complete
(like for example uploading a large glance image, which
can easily take hours before the API responds).

https://bugzilla.suse.com/show_bug.cgi?id=897902
(cherry picked from commit 81f815bcf37823a2f15dabcd780b8e882b2233c4)