Pylint is not for chickens.

Called method is setting up response code 503 in case of cache being empty. So
check it out before preparing success response.

This reverts commit b165f75e.

Otherwise real system is not tested, and so caches are not invalidated
(and not tested)

Don't hack just because you want pyflakes to pass.

Also update doc

It is required now to call vifib_solve_automatically alarm after
delivery causality update.

Check divergence (for calculating and building) really often and while checking only move to one of possible states (solved or diverged).

For diverged ones try rarely to solve divergence automatically.

Now just requesting software installation on computer makes related SR
available immediately on computer.