Merge branch 'jn/maint-gitweb-utf8-fix' into maint

* jn/maint-gitweb-utf8-fix: gitweb: Fix fallback mode of to_utf8 subroutine gitweb: Output valid utf8 in git_blame_common('data') gitweb: esc_html() site name for title in OPML gitweb: Call to_utf8() on input string in chop_and_escape_str()