Enable erp5-bin as external repository

This repository for holding the BT which not suitable to put
in erp5 main repository

stack/erp5/buildout.cfg

@@ -343,6 +343,11 @@ link-binary =
 [template-haproxy-cfg]
 <= download-base
 
+[erp5-bin]
+<= erp5
+repository = https://lab.nexedi.com/nexedi/erp5-bin.git
+branch = master
+
 [bt5-repository]
 # Format:
 #   <url or path> [...]
@@ -354,7 +359,7 @@ list = ${local-bt5-repository:list}
 [local-bt5-repository]
 # Same as bt5-repository, but only local repository.
 # Used to generate bt5lists.
-list = ${erp5:location}/bt5 ${erp5:location}/product/ERP5/bootstrap
+list = ${erp5:location}/bt5 ${erp5:location}/product/ERP5/bootstrap ${erp5-bin:location}/bt5
 
 [genbt5list]
 recipe = plone.recipe.command
@@ -365,7 +370,7 @@ command =
 update-command = ${:command}
 
 [erp5_repository_list]
-repository_id_list = erp5
+repository_id_list = erp5 erp5-bin
 
 # ERP5 defaults, which can be overridden in inheriting recipes (e.g. wendelin)
 [erp5-defaults]