Template:Shared utf8 functions

• utfChar
• utfCode
• utfLen
• utfSeek
• utfSub
• utf8.byte
• utf8.char
• utf8.charpos
• utf8.escape
• utf8.find
• utf8.fold
• utf8.gmatch
• utf8.gsub
• utf8.insert
• utf8.len
• utf8.lower
• utf8.match
• utf8.ncasecmp
• utf8.next
• utf8.remove
• utf8.reverse
• utf8.sub
• utf8.title
• utf8.upper
• utf8.width
• utf8.widthindex