Add "context object" when connecting lambda
Add "context object" when connecting lambda

By adding a "context object" the connection will be removed when
the object is deleted.

OpenChemistry/tomviz,cjh1/tomviz,mathturtle/tomviz,OpenChemistry/tomviz,OpenChemistry/tomviz,mathturtle/tomviz,cryos/tomviz,OpenChemistry/tomviz,cjh1/tomviz,cryos/tomviz,mathturtle/tomviz,cjh1/tomviz,thewtex/tomviz,thewtex/tomviz,cryos/tomviz,thewtex/tomviz