Remove inheritance from Hash in FilterHash

introduce FilterList as base class for `exclude` and `include` list;
move and rename InclusionFilterHash & ExclusionFilterHash to
InclusionList & ExclusionList;
hide all difference between InclusionList & ExclusionList inside
this class;
remove FilterManager.inspect_filter_hash;
resolve issue with different version of Ruby & reject/select
fix #include_example? method in ExclusionList, return
empty lines to warnings.rb file
remove forwadable module from filter list,
set strict list of methods for a filter list,
update related rspec specs