BUG: Coverity 1103595: Uninitialized pointer field

Also cleanup some style in itkVoronoiDiagram2DGenerator.h.

Change-Id: I88dd1262ae319ac6204262b21c409b23a75f82b0
BUG: Coverity 1081508: Uninitialized pointer field

Initialize member variable "ReceptorMemberCommand::m_This".

Also cleanup style of other constructor initializer lists in itkCommand.h.

Change-Id: Ia3d9e183cf2b7aa5079edf937f39b6ef25cb8926
Merge topic 'cov_1081508'

e6226461 BUG: Coverity 1081508: Uninitialized pointer field
Merge topic 'cov_1103595'

aa41b035 BUG: Coverity 1103595: Uninitialized pointer field