point libwally to my own branch

Author: instagibbs

.gitmodules

@@ -9,8 +9,9 @@
 	url = https://github.com/ianlancetaylor/libbacktrace.git
 [submodule "external/libwally-core"]
 	path = external/libwally-core
-	url = https://github.com/ElementsProject/libwally-core.git
+    url = https://github.com/instagibbs/libwally-core.git
 	ignore = dirty
+    branch = keyspend_support
 [submodule "external/gheap"]
 	path = external/gheap
 	url = https://github.com/valyala/gheap