* helper method to detect disconnected state
* clear ATC info if disconnected or not available
* unit test for "finders"
* added Doxygen file
* formatting frequency in text message tabs
CSequence uses std::find, and CCollection uses the more efficient find method of the implementation type,
which requires that the implementation type be an associative container like QSet or std::set.
Modified CContainerBase::contains to use these new find methods.
