Fixed bug with string parsing in C/C++

[rogerhub]

There are 2 bugs fixed here:

1. The tokenizer did not recognize characters in the \xHH format. For
   example, '\x10'
2. The tokenizer interpreted '\0x10' as a proper character, which should
   actually be interpreted as '\0', 'x', '1', '0' (4 characters), which
   would not be valid if written as '\0x10'.

Here is some sample input for testing: (save as file.c)

'\x30'

With the bugged version, I would get error messages similar to:

  Scanning Error in 'file.c':
  Lexical error at line 1, column 3.  Encountered: "x" (120), after : "\'\\"

[rogerhub]

Also, it looks like a character string like '\r\n' is valid (source), but its value is implementation-dependent. Would you accept a patch that enabled support for those?

[lama0206]

Yes. Because JPlag does not compile the program, the values are not important.