installation: PyLD to 0.5.0
installation: PyLD to 0.5.0

* Using inveniosoftware's fork with has a special version number
  26.0.5.0-dev to prevent further updates to override it.

Signed-off-by: Yoan Blanc <7e8c88beed64bd6a341c3085bc82ac100e832f6e@cern.ch>

tiborsimko/invenio,tiborsimko/invenio,inveniosoftware/invenio,inveniosoftware/invenio