Fix properties on PlotMatrixView.

Needed to fix widgets and property signatures for properties on the
PlotMatrixView.

Change-Id: I21fb539fd2fad8776c24ee3bbd259fcdbe859049
Backwards compatibility fixes for ColorAttributeType.

We now support complete backwards compatibily for ColorAttributeType and
ColorArrayName in Python. Also fixed logic to backwards compatibility in
Python. ParaView Python package scripts should no longer set the
compatibility to anything. User scripts, however can explicitly request
compatibility to older version.

Change-Id: Ib2b1b925d51586a455c6a52530a55f5a977554ed
Merge topic 'lookup_table_cleanup' into next

72ec4ef2 Backwards compatibility fixes for ColorAttributeType.
19b6654a Fix properties on PlotMatrixView.
Merge topic 'fix_documentation_typo' into next

7641997a Fix typo in documentation (thanks Jean Favre).