Merge PR #147：Round substring positions with XPath round() function
Merge PR #130: Fix `name*expr` lexing XPath §3.7 specification
Merge PR #124
fix #121
Merge PR #117
Merge PR #111
fix non-English characters query: #106, #99
fix #104
#98. remove the duplicate elements filter, avoid `htmlquery` and `xml… …query` packages re-use the cached element in some cases. #94
docs: update `lower-case()` fuction. close #95