Make building with flatpak-builder possible

.gitignore

+builddir
+.flatpak-builder

README.md

@@ -19,6 +19,13 @@ The easiest and most convenient way is to build _briar-gtk_ using
 In _Builder_, click "Clone Repository" at the bottom and
 enter the URL to this Git project.
 
+You can also call this:
+```bash
+flatpak remote-add --user --if-not-exists flathub https://flathub.org/repo/flathub.flatpakrepo
+flatpak-builder builddir --install-deps-from=flathub --user --install --force-clean --ccache app.briar.gtk.json
+flatpak run app.briar.gtk
+```
+
 ## Design Goals
 
 * Intuitive UI that follows the Briar Android client

app.briar.gtk.json

@@ -14,6 +14,7 @@
         "--socket=wayland",
         "--filesystem=xdg-run/dconf",
         "--filesystem=~/.config/dconf:ro",
+        "--filesystem=~/.briar",
         "--talk-name=ca.desrt.dconf",
         "--env=DCONF_USER_CONFIG_DIR=.config/dconf",
         "--env=PATH=/app/bin:/usr/bin:/app/jre/bin"
@@ -108,7 +109,7 @@
             "sources": [
                 {
                     "type": "git",
-                    "url": "file:///home/nico/Work/Current/Briar/briar-gtk"
+                    "url": "https://code.briarproject.org/NicoAlt/briar-gtk.git"
                 }
             ]
         }