Add macro file for configure time developer mode flag

build-aux/que_developer_mode.m4

@@ -0,0 +1,19 @@
+# Like AM_MAINTAINER_MODE, but doesn't touch automake internals and so
+# can be used freely to control access to project specific developer
+# tooling without breaking autotools if disabled.
+AC_DEFUN([QUE_DEVELOPER_MODE], [
+        m4_case(m4_default([$1], [disable]),
+                [enable], [m4_define([_que_developer_def], [disable])],
+                [disable], [m4_define([_que_developer_def], [enable])],
+                [m4_define([_que_developer_def], [enable])
+                m4_warn([syntax], [unexpected argument to AM@&t@_DEVELOPER_MODE: $1])])
+        AC_MSG_CHECKING([whether to enable developer-specific portions of Makefiles])
+        AC_ARG_ENABLE([developer-mode],
+                [AS_HELP_STRING([--]_que_developer_def[-developer-mode],
+                        _que_developer_def[ dependencies and make targets only useful for developers])],
+                [USE_DEVELOPER_MODE=$enableval],
+                [USE_DEVELOPER_MODE=]m4_if(_que_developer_def, [enable], [no], [yes]))
+        AC_MSG_RESULT([$USE_DEVELOPER_MODE])
+        AM_CONDITIONAL([DEVELOPER_MODE], [test $USE_DEVELOPER_MODE = yes])
+
+])