[BUGFIX]Subcontent's length is the same to subquery's length
Initialize instance variables for stepping over in #initialize
Add todo comment about variable name
Implement search with stepping over end tag
Make XHTML::Searcher#detect_stepping_over private
[REFACTORING]Extract method #find_from_content from #search
[REFACTORING]Insert line breaks for readability
Add test_stepping_over_start_and_end_tag