Log Message:
Update wip/xfconf to 4.8.1

Upstream changes:

Xfconf 4.8.1
============

  * Fix double free crash (bug #8169).
  * Fix compiler warnings on solaris.
  * Avoid gcc 4.6 compiler warning.
  * Allow installation of the helpers in a custom location.
  * Updated translations: hr, is, ko, ms, nl, ru, sk, te, tr, zh_CN.