refactor scanner
rename lastTokenCol to lastTokenColumn
rename scanner.NextRaw() to scanner.scanRaw()
optimize scanner stash verification
remove all whitespaces with new line
refactor parser.Parser
rename parser.StringParser(string) to parser.NewStringParser(string)
rename parser.FileParser(string) to parser.NewFileParser(string)
rename parser.advance() to parser.scanToken()
rename parser.parse() to parser.parseToken()
refactor parser.Parse()