Add the gui submodule.

Add the gui submodule.

diff --git a/.gitmodules b/.gitmodules
new file mode 100644
index 0000000..db96f9b
--- /dev/null
+++ b/.gitmodules
@@ -0,0 +1,3 @@
+[submodule "gui"]
+	path = gui
+	url = https://github.com/GrangerHub/Stellar-Prey-GUI.git
diff --git a/gui b/gui
new file mode 160000
index 0000000..7e960a3
--- /dev/null
+++ b/gui
@@ -0,0 +1 @@
+Subproject commit 7e960a36f7a8c6cf662cda239cb65bc635c9ea94

GitHub
sha: 553678c5