Modify version check during package upgrade

Modify version check during package upgrade

Cynara has to determine its currently installed version during package
upgrade. Doing RPM queries from inside install-time scripts isn't
recommended. Necessary information is obtained from Cynara's version
information.

However, not all Cynara releases provided mechanism of reporting its
version. In case of lack of it, following fallback mechanism is
provided: version information is extracted from a name of a file that
Cynara depends on, which currently is
"<libdir>/libcynara-commons.so.<version>".

Change-Id: I5c9a2abf123d91a32513980e3f9c24112d59547c