webapp/jupyter2: some bugfixes
webapp/jupyter2: some bugfixes

tscholl2/smc,sagemathinc/smc,sagemathinc/smc,sagemathinc/smc,sagemathinc/smc,tscholl2/smc,tscholl2/smc,DrXyzzy/smc,DrXyzzy/smc,tscholl2/smc,tscholl2/smc,DrXyzzy/smc,DrXyzzy/smc