[gnome-builder] update gitignore

[Christian Hergert <chergert src gnome org>]

commit 3332cb319e290459386a6bb41b1efb241da2b1b1
Author: Christian Hergert <chergert redhat com>
Date:   Mon May 8 12:54:44 2017 -0700

    update gitignore
    
    These should not be created with make run, but in case we run by handl, it
    is easy enough to hide all of them.

 Makefile.am |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)
---
diff --git a/Makefile.am b/Makefile.am
index 74992d6..f57bed8 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -19,6 +19,7 @@ GITIGNOREFILES =                                                               \
        **/*.swp                                                               \
        .flatpak-builder                                                       \
        *.o                                                                    \
+       **/__pycache__                                                         \
        aclocal.m4                                                             \
        build-aux                                                              \
        ChangeLog                                                              \