add namespace deprecated for dtkVector3D
add namespace deprecated for dtkVector3D

NicolasSchnitzler/dtk,rdebroiz/dtk,d-tk/dtk,rdebroiz/dtk,d-tk/dtk,NicolasSchnitzler/dtk,d-tk/dtk,d-tk/dtk,d-tk/dtk,d-tk/dtk,rdebroiz/dtk,NicolasSchnitzler/dtk,NicolasSchnitzler/dtk,rdebroiz/dtk