cleanup compilation warnings
Properties do not support any type:
../libgitg/gitg-commit-model.vala:116.3-116.35: warning: Type `Ggit.OId[]' can not be used for a GLib.Object property
public Ggit.OId[] permanent_lanes { get; set; }
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
../libgitg/gitg-diff-view-file-selectable.vala:48.2-48.28: warning: Type `int[]' can not be used for a GLib.Object property
public int[] selected_lines
^^^^^^^^^^^^^^^^^^^^^^^^^^^
../libgitg/gitg-diff-view.vala:651.2-651.28: warning: Type `Gitg.PatchSet[]' can not be used for a GLib.Object property
public PatchSet[] selection
^^^^^^^^^^^^^^^^^^^^^^^^^^^
../libgitg/gitg-repository-list-box.vala:613.3-613.24: warning: Type `Gitg.RepositoryListBox.Row[]' can not be used for a GLib.Object property
public Row[] selection
^^^^^^^^^^^^^^^^^^^^^^