ConfigWrapper class introduced: sharing of the same ConfigReader object between JailsReader and JailReader (don't read jail config each jail);
sharing of the same DefinitionInitConfigReader (ActionReader, FilterReader) between all jails using that;
cache of read a config files was optimized;
test case extended for all types of config readers;
Merge remote-tracking branch 'sebres:cache-config-read-820' into ban-time-incr