[frogr] flatpak: add build script

[Mario Sanchez Prada <msanchez src gnome org>]

commit ff2bc3e95cad170540d6ac58d3273707b943f755
Author: Mario Sanchez Prada <msanchez gnome org>
Date:   Sat May 20 23:00:35 2017 +0100

    flatpak: add build script

 flatpak/build-flatpak.sh |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)
---
diff --git a/flatpak/build-flatpak.sh b/flatpak/build-flatpak.sh
new file mode 100755
index 0000000..e0defcc
--- /dev/null
+++ b/flatpak/build-flatpak.sh
@@ -0,0 +1,3 @@
+#!/bin/bash
+
+flatpak-builder --force-clean --ccache --require-changes --repo=repo app $1