make: Disable DEVELOPER by default

We had quite a few users running into issues because the `--dev-xyz` options and
`dev-xyz` RPC calls were available. Before a release we should make sure that
the default compilation flags are safe.

Signed-off-by: Christian Decker <decker.christian@gmail.com>

Makefile

@@ -18,7 +18,7 @@ VALGRIND_TEST_ARGS = --track-origins=yes --leak-check=full --show-reachable=yes
 endif
 
 # By default, we are in DEVELOPER mode, use DEVELOPER= on cmdline to override.
-DEVELOPER := 1
+DEVELOPER := 0
 
 ifeq ($(DEVELOPER),1)
 DEV_CFLAGS=-DDEVELOPER=1 -DCCAN_TAL_DEBUG=1 -DCCAN_TAKE_DEBUG=1