Remove dead dependency of http_parser on httpc

Http_parser is a standalone library, which in fact does not
require httpc. And because of that it is going to be moved into
lib/http_parser.

src/http_parser.c

@@ -30,7 +30,6 @@
  */
 
 #include <string.h>
-#include "httpc.h"
 #include "http_parser.h"
 
 #define LF     (unsigned char) '\n'