[pitivi] Update POTFILES.in and POTFILES.skip

[Piotr Drąg <piotrdrag src gnome org>]

commit 76b19b17f5e9fc530537201cb6ad72679313e2e9
Author: Piotr Drąg <piotrdrag gmail com>
Date:   Wed Sep 6 01:08:19 2017 +0200

    Update POTFILES.in and POTFILES.skip

 po/POTFILES.in   |    1 +
 po/POTFILES.skip |    1 +
 2 files changed, 2 insertions(+), 0 deletions(-)
---
diff --git a/po/POTFILES.in b/po/POTFILES.in
index 284eda3..bcaa84e 100644
--- a/po/POTFILES.in
+++ b/po/POTFILES.in
@@ -6,6 +6,7 @@ data/pitivi.desktop.in
 [type: gettext/glade]data/ui/alignmentprogress.ui
 [type: gettext/glade]data/ui/clipmediaprops.ui
 [type: gettext/glade]data/ui/cliptransformation.ui
+[type: gettext/glade]data/ui/customwidgets/alpha.ui
 [type: gettext/glade]data/ui/depsmanager.ui
 [type: gettext/glade]data/ui/effectslibrary.ui
 [type: gettext/glade]data/ui/elementsettingsdialog.ui
diff --git a/po/POTFILES.skip b/po/POTFILES.skip
index 88b6148..8f73642 100644
--- a/po/POTFILES.skip
+++ b/po/POTFILES.skip
@@ -1,3 +1,4 @@
 # List of source files that should *not* be translated.
 # Please keep this file sorted alphabetically.
+tests/plugins/test_alpha.ui
 tests/test_media_library.py