fixup after c5e509c3

Slapos.libnetworkcache is added after bin/buildout has already
been generated. The fixup consists of adding libnetworkcache in
bin/buildout from bin/python.
bin/python has been renamed to bin/python.temp until the end of
bootstrap to start again if we fail before the end of the task.

obs/re6st/buildout.cfg.in

@@ -17,7 +17,7 @@ parts += chrpath python
 
 [python]
 recipe = zc.recipe.egg
-interpreter = ${:_buildout_section_name_}
+interpreter = ${:_buildout_section_name_}.tmp
 eggs = slapos.libnetworkcache
 # https://lab.nexedi.com/nexedi/slapos.buildout/merge_requests/11
 scripts = dummy

obs/re6st/make.py

@@ -97,6 +97,8 @@ def bootstrap(task):
                 "--setuptools-version", "33.1.0"), input=bootstrap)
             check_call(("bin/buildout", "buildout:extensions=",
                 "buildout:newest=true", "buildout:parts=python"))
+            check_call(("bin/python.tmp", "bin/buildout", "bootstrap"))
+            os.rename("bin/python.tmp", "bin/python")
 
 def sdist_version(egg):
     global MTIME, VERSION