cJSON_Parse("") should return 0.

git-svn-id: http://svn.code.sf.net/p/cjson/code@35 e3330c51-1366-4df0-8b21-3ccf24e3d50e

cJSON.c

@@ -230,7 +230,7 @@ static const char *parse_object(cJSON *item,const char *value);
 static char *print_object(cJSON *item,int depth,int fmt);
 
 /* Utility to jump whitespace and cr/lf */
-static const char *skip(const char *in) {while (in && (unsigned char)*in<=32) in++; return in;}
+static const char *skip(const char *in) {while (in && *in && (unsigned char)*in<=32) in++; return in;}
 
 /* Parse an object - create a new root, and populate. */
 cJSON *cJSON_Parse(const char *value)