XXX try slapos rebootstrap patches

stack/slapos.cfg

@@ -41,6 +41,7 @@ find-links +=
   http://www.nexedi.org/static/packages/source/
   http://www.nexedi.org/static/packages/source/hexagonit.recipe.download/
   http://www.nexedi.org/static/packages/source/slapos.buildout/
+  https://lab.nexedi.com/jerome/slapos.rebootstrap/raw/7371a539ee72639be921f19d25ab845e752b707d/dist/slapos.rebootstrap-4.4b0.tar.gz
 
 # Use only quite well working sites.
 allow-hosts +=
@@ -60,6 +61,7 @@ allow-hosts +=
   sourceforge.net
   www.dabeaz.com
   www.owlfish.com
+  lab.nexedi.com
 
 # Use an https index
 index = https://pypi.org/simple/
@@ -142,7 +144,7 @@ slapos.core = 1.5.7
 slapos.extension.strip = 0.4
 slapos.extension.shared = 1.0
 slapos.libnetworkcache = 0.20
-slapos.rebootstrap = 4.3
+slapos.rebootstrap = 4.4b0
 slapos.recipe.build = 0.42
 slapos.recipe.cmmi = 0.12
 slapos.toolbox = 0.104