Added Content-type: application/vnd.api+json (#513)

The content should be well formed JSON and it will make NAXSI not complain about Unknown Format.
Can help many other users.

naxsi_src/naxsi_runtime.c

@@ -2334,6 +2334,11 @@ ngx_http_dummy_body_parse(ngx_http_request_ctx_t *ctx,
 			    (u_char *) "application/json", 16)) {
     ngx_http_dummy_json_parse(ctx, r, full_body, full_body_len); 
   }
+  /* 24 = echo -n "application/vnd.api+json" | wc -c */
+  else if (!ngx_strncasecmp(r->headers_in.content_type->value.data,
+                (u_char *) "application/vnd.api+json", 24)) {
+    ngx_http_dummy_json_parse(ctx, r, full_body, full_body_len);
+  }
   /* 22 = echo -n "application/csp-report" | wc -c */
   else if (!ngx_strncasecmp(r->headers_in.content_type->value.data,
                             (u_char *) "application/csp-report", 22)) {