SSL_INSECURE support and usage added

include/curl/curl.h

@@ -197,6 +197,8 @@ typedef enum {
   CURLE_SEND_ERROR,              /* 55 - failed sending network data */
   CURLE_RECV_ERROR,              /* 56 - failure in receiving network data */
   CURLE_SHARE_IN_USE,            /* 57 - share is in use */
+  CURLE_SSL_INSECURE,            /* 58 - connect attempt without certificate
+                                    but SSL_INSECURE not explicitly allowed */
   CURL_LAST /* never use! */
 } CURLcode;
 
@@ -571,6 +573,9 @@ typedef enum {
   /* Provide a CURLShare for mutexing non-ts data */
   CINIT(SHARE, OBJECTPOINT, 100),
 
+  /* Explicitly allow insecure SSL connects */
+  CINIT(SSL_INSECURE, LONG, 101),
+
   CURLOPT_LASTENTRY /* the last unused */
 } CURLoption;