Plugin EULA

Plugins now support EULA.

An EULA text file can be added to a plugin as follows:

add_paraview_plugin(EULATestPlugin "0.1"
  REQUIRED_ON_CLIENT
  SERVER_MANAGER_XML EULATestPlugin.xml
  EULA EULA.txt)

EULA is auto accepted on command line tools, with the following message:

-----------------------------------------------------
  By loading the 'EULATestPlugin' plugin you have accepted the EULA shipped with it.
  If that is not acceptable, please restart the application without loading 
  the 'EULATestPlugin' plugin.
-----------------------------------------------------

In ParaView desktop client, you see the following prompt when the plugin is loaded

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Backport: release