Add optional column for players uuids (#1840)

src/main/java/fr/xephi/authme/util/UuidUtils.java

@@ -0,0 +1,27 @@
+package fr.xephi.authme.util;
+
+import java.util.UUID;
+
+/**
+ * Utility class for various operations on UUID.
+ */
+public final class UuidUtils {
+
+    // Utility class
+    private UuidUtils() {
+    }
+
+    /**
+     * Returns whether the given string as an UUID or null
+     *
+     * @param string the uuid to parse
+     * @return parsed UUID if succeed or null
+     */
+    public static UUID parseUuidSafely(String string) {
+        try {
+            return UUID.fromString(string);
+        } catch (IllegalArgumentException | NullPointerException ex) {
+            return null;
+        }
+    }
+}