subrepo: use per-type config options to enable subrepos We change subrepos.allowed from a list of allowed subrepo types to a combination of a master switch and per-type boolean flag. If the master switch is set, subrepos can be disabled wholesale. If subrepos are globally enabled, then per-type options are consulted. Mercurial repos are enabled by default. Everything else is disabled by default.

--- a/tests/test-mq-subrepo-svn.t	Mon Nov 06 14:56:17 2017 -0500
+++ b/tests/test-mq-subrepo-svn.t	Mon Nov 06 22:32:41 2017 -0800
@@ -6,7 +6,8 @@
   > [diff]
   > nodates = 1
   > [subrepos]
-  > allowed = hg, svn
+  > allowed = true
+  > svn:allowed = true
   > EOF
 
 fn to create new repository, and cd into it