Adding a key to indicate the current process has the block

Change-Id: Ic1e954d3cb7ab604ff9da34b0ff9e3147ed4f4e1
Legacy reader/writers for composite data now save field data

Change-Id: I0ba1be17ee37db3803bc0574071c1f6ea281c38c
Merge topic 'vtk_bugs_and_information_keys' into master

0caa9368 Legacy reader/writers for composite data now save field data
da65eea4 Adding a key to indicate the current process has the block