Refactored how pieces and extents are handled.

Refactoring the way VTK goes between piece and structured
extents. Before, extent translators were used when the pipeline
moved from structured to unstructured data converting piece
request to extent request. This caused many problems with filters
that altered extents, mainly a lot of redundant IO due to
repartitioning of different extents. This became extremely
cumbersome to manage when running distributed. The new behavior
pushes the extent translation all to way to the readers and
only when readers are able to read a subset. This works much
better. The only downside is that filters need to be able to
handle data extents different than update extents. Most filters
can do this but many imaging filters cannot. Those that are
needed in parallel will have to be updated.

As part of this work, I also removed MAXIMUM_NUMBER_OF_PIECES
and added CAN_HANDLE_PIECE_REQUEST. MAXIMUM_NUMBER_OF_PIECES had
reduced to being a boolean. 1 for serial sources, -1 for parallel
sources. I removed it and added a CAN_HANDLE_PIECE_REQUEST instead.
This key, produced by a source, tells the executive that a source is
able to handle piece request. It is a source only key produced in
RequestInformation and is not propagated downstream. If this key is
not present, the executive will only execute the source for piece 0
to produce the entire data. It is then up to the user to add a filter
that splits the data for other piece requests. The only exception to
this is when CAN_PRODUCE_SUB_EXTENT is present, in which case the
executive will split using an extent translator AT THE source - not
downstream.

Conflicts:
	ParaViewCore/ServerImplementation/Core/vtkSISourceProxy.cxx
	ParaViewCore/ServerImplementation/Core/vtkSISourceProxy.h
	ParaViewCore/VTKExtensions/Core/CMakeLists.txt
	ParaViewCore/VTKExtensions/Testing/ParaViewCoreVTKExtensionsPrintSelf.cxx
	Plugins/PrismPlugins/vtkPrismSurfaceReader.cxx
	Qt/Components/Resources/UI/pqApplicationOptions.ui
	Qt/Components/pqApplicationOptions.cxx
	Qt/Core/pqServer.cxx
	VTK

Change-Id: I4763c07aae0e0c3f64c8c0adad40dd4a09720b5e
plugins: only include tested languages

The plugin tests were always enabled because they were always searched
for. Instead, search for the testing languages.

Change-Id: I974e63270bfc9b589706fd8a9b6e8bb59ab82b25
plugins: allow static plugins to be loaded dynamically

Change-Id: I9fc37d4ef87534cbc159d72e734ea6bda35985ca
plugins: enable the plugin dialog in static builds

Change-Id: I4164bcae4334c91114f512fc658c3588088c06f2
Add option to exclude ParaViewData target from default build

Add a "PARAVIEW_DATA_EXCLUDE_FROM_ALL" option to cause the ParaViewData
to be marked with the EXCLUDE_FROM_ALL property so that it does not
build unless explicitly requested by the user.  This may be useful to
developers that want to get ParaView built locally without waiting for
all the test data to download.

Within a dashboard build, hard-code the option to OFF since dashboards
need the data.  Otherwise, select a default based on local
configuration.  Teach the SetupExternalData developer setup script to
prompt for a default.  If that does not provide one, check for an
environment variable.  Otherwise, fall back to a default of OFF so that
the basic build and test sequence works without extra steps.

When the option is ON at the same time as BUILD_TESTING, produce a
warning that a manual step may be needed after building and before
running tests.

Change-Id: I5c3e60a827176a441e86d360f5d1f141946027d3
Fix SaveColorMap test failure

The commit discretize_color added a line in the Color Map Editor panel,
and it seems that now a scroll bar appears in some cases, so a mouse click
from the test was incorrectly positionned.

Change-Id: I818beb351ae8a16a57cde7c075b6518238f2429c
Fixed compile error.

Change-Id: Ib2f034d079a0cf08f3924856de07a71d57e747f2
Fixed catalyst configure error.

Catalyst editions needs to be made aware of the change in
location of parallel XML writers.
Merge topic 'data-download-without-testing'

7f2ee05e plugins: only include tested languages
Merge topic 'discretize_color'

1d0e3553 Fix SaveColorMap test failure
Merge topic 'manual-ParaViewData-option'

29e4cc2c Add option to exclude ParaViewData target from default build
Merge topic 'refactor-piece-and-extent'

7b67e069 Fixed catalyst configure error.
da5bd323 Fixed compile error.
89fbd7ef Refactored how pieces and extents are handled.
Merge topic 'static-plugins'

a6069df3 plugins: enable the plugin dialog in static builds
43f9ae27 plugins: allow static plugins to be loaded dynamically