[pitivi] Update .gitignore

[Thibault Saunier <tsaunier src gnome org>]

commit e39a26848e5894fc10f1fc5357a59ea72e5389c1
Author: Thibault Saunier <tsaunier gnome org>
Date:   Thu Dec 17 11:24:12 2015 +0100

    Update .gitignore

 .gitignore |    7 +++++++
 1 files changed, 7 insertions(+), 0 deletions(-)
---
diff --git a/.gitignore b/.gitignore
index 1fe4640..734e22d 100644
--- a/.gitignore
+++ b/.gitignore
@@ -33,6 +33,7 @@ pitivi/coptimizations/.deps/
 po/POTFILES
 po/stamp-it
 py-compile
+*__pycache__*
 
 # Generated by make
 *.la
@@ -52,6 +53,7 @@ po/.intltool-merge-cache
 
 # Generated by make check
 po/pitivi.pot
+tests/samples/*.proxy.mkv
 
 # Generated when running the project
 *.pyc
@@ -62,3 +64,8 @@ pitivi/libpitivi/.libs/*
 *.gir
 *.typelib
 prebuilt/
+
+# xdg-app
+build/xdg-app/.xdg-app-builder/
+build/xdg-app/pitivi-*.json
+build/devel/