Print embedded obj in one line

If you call cso_get_string to generate a string representation
of the content of a cso_obj_t an embedded array or struct (dict)
is written into a single line if it is less than 32 bytes in size.

The formatting of cso_get_string is changed.
Contained elements start with one more space character
than struct or array delimiters:

        cso_obj_t * obj = 0 ;
        char      * str = 0 ;
        cso_new(&obj, CSO_DICT, 128) ;
        cso_add_str(obj, "greeting", "Hello World") ;
        cso_add_obj(obj, "array", CSO_ARRAY) ;
        cso_add_u32(obj, 0, 1) ;
        cso_add_u32(obj, 0, 2) ;
        cso_add_u32(obj, 0, 3) ;
        cso_end(obj) ;
        cso_get_string(obj, &str) ;
        printf("%s\n", str) ;

The above program now prints:

{
 "greeting": "Hello World",
 "array": [ 1, 2, 3 ]
}