Add missing dots at the end of exception messages

Author: fabpot

Filesystem.php

@@ -103,7 +103,7 @@ public function mkdir($dirs, $mode = 0777)
                     if (self::$lastError) {
                         throw new IOException(sprintf('Failed to create "%s": %s.', $dir, self::$lastError), 0, null, $dir);
                     }
-                    throw new IOException(sprintf('Failed to create "%s"', $dir), 0, null, $dir);
+                    throw new IOException(sprintf('Failed to create "%s".', $dir), 0, null, $dir);
                 }
             }
         }
@@ -362,7 +362,7 @@ public function hardlink($originFile, $targetFiles)
         }
 
         if (!is_file($originFile)) {
-            throw new FileNotFoundException(sprintf('Origin file "%s" is not a file', $originFile));
+            throw new FileNotFoundException(sprintf('Origin file "%s" is not a file.', $originFile));
         }
 
         foreach ($this->toIterable($targetFiles) as $targetFile) {