new format specifiers for request string

I modified the parser to take into account the request strings with no surrounding delimiters, as single quotes, double quotes or anything else. Without those delimiters, the parser find no valid log entry because of white spaces.
I added new format specifiers : %m for request method, %U for uri and %H for request protocol.

So a valid log_format string could be 
"%h" - - [%d] %m %U %H "%s" %b "%^" "%u" "%^" "%^" "%T"
in place of 
"%h" - - [%d] %r "%s" %b "%^" "%u" "%^" "%^" "%T"


best regards,