add FineDiff dependency

& Composer metadata

& two WMF patches applied, see sites/all/modules/donor_review/FineDiff-*.patch

Change-Id: I4972e8d4e6fc3a0ac054e0501ba5a78d6f6df476
Fix dependency bug by converting to Drupal autoload style

Change-Id: I05e3823a7c8476abcbc2254a6aba2db62f41f050
Merge "Fix dependency bug by converting to Drupal autoload style"