fixed typo

README.md

@@ -73,7 +73,7 @@ Contributing security advisories is as easy as it can get:
             issue is not fixed yet (most of the time, the date of the commit
             that fixed the issue in the following format `2012-08-27 19:17:44`)
             -- this information must be as accurate as possible as it is used
-            to determined if a software is affected or not;
+            to determine if a project is affected or not;
 
           * `versions`: An array of constraints describing affected versions
             for this branch (this is the same format as the one used for

validator.php

@@ -162,7 +162,7 @@ protected function execute(InputInterface $input, OutputInterface $output)
                         }
                     }
 
-                    if (!isset($branch['time'])) {
+                    if (!array_key_exists('time', $branch)) {
                         $messages[$path][] = sprintf('Key "time" is required for branch "%s".', $name);
                     }