Integrate coverity scans in dbus travis-ci

Submitted by Ralf Habacker @rhabacker

Assigned to D-Bus Maintainers

Link to original bug (#105689)

Description

dbus is registered at coverity (https://scan.coverity.com/projects/dbus), at travis-ci (https://travis-ci.org/d-bus/dbus) and github (https://github.com/d-bus/dbus), which makes it possible to run coverity scans on a regular interval very easily. The related howto is located at https://scan.coverity.com/travis_ci

Version: git master