rename msg.h to Msg.h, rename arg_parser.h to ArgParser.h. And change files' including filename changed
[refactor] prettify ?: operator layout to if-else style. [refactor] expand too long oneline method
remove uselses percent_count method
add cstr::size() equilent to cstr::length()
rename char_count to count_char
add a failure test for new variadic args version bit_at
pass the test of variadiac args version bit_at
adjust comment position in cargseq::any_arg_seq
any_arg_seq's id arg is used more often than escape, pull it front