Add 'default' foward proxy worker to the proxy_server_conf.

    struct apr_sockaddr_t *addr;

};

typedef struct proxy_balancer  proxy_balancer;

typedef struct proxy_worker    proxy_worker;

typedef struct proxy_conn_pool proxy_conn_pool;

typedef struct {

    apr_array_header_t *proxies;

    apr_array_header_t *sec_proxy;

    apr_array_header_t *allowed_connect_ports;

    apr_array_header_t *workers;

    apr_array_header_t *balancers;

    proxy_worker       *forward;    /* forward proxy worker */

    const char *domain;     /* domain name to use in absence of a domain name in the request */

    int req;                /* true if proxy requests are enabled */

    char req_set;

    apr_pool_t *pool;           /* Pool used for allocating this struct */

} proxy_server_conf;

typedef struct proxy_balancer  proxy_balancer;

typedef struct proxy_worker    proxy_worker;

typedef struct proxy_conn_pool proxy_conn_pool;

typedef struct {

    const char *p;            /* The path */