Fix bug preventing adding nodes to a slice.
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sfa-GITPATH := git://git.onelab.eu/sfa.git@sfa-1.0-25
-sface-GITPATH := git://git.onelab.eu/sface.git@sface-0.1-14
+sface-GITPATH := git://git.onelab.eu/sface.git@sface-0.1-15
nodeconfig-GITPATH := git://git.onelab.eu/nodeconfig.git@nodeconfig-5.0-5
bootmanager-GITPATH := git://git.onelab.eu/bootmanager.git@bootmanager-5.0-19
pypcilib-GITPATH := git://git.onelab.eu/pypcilib.git@pypcilib-0.2-10