Fixing hash typo on Cookie#add
build_xpath never receives index, remove dead code
make :xpath and :css equal

now both of them work on all elements and can be combined with the same
selectors
bump watirspec
changelog for :css selector improvements
improvements to YARD macro and attribute handler

1. replace YARD handler with YARD macro
2. explicitly define IDL attribute on class attribute
3. prefer IDL attribute over content attribute
4. removed ‘#html_for’ method
5. deprecate ‘#colspan’ and ‘#rowspan’ methods