Initial changes to support Qt5

Added a new flag called PARAVIEW_QT_VERSION that can be set to either 4 or 5.
Depending on the value of this flag, the appropriate Qt version is looked for
and built against.

If PARAVIEW_QT_VERSION==5, the necessary Qt5 modules can be
imported by including the script "ParaViewQt5.cmake". This script also sets
important Qt variables used throughout the project.

Setting the officially supported version of Qt5 to 5.0.2. Although, paraview
compiles fine against Qt-5.0.0, there are known issues that prevent it from
being fully functional (https://bugreports.qt-project.org/browse/QTBUG-28872).
Setting the minimum Qt5 version to 5.0.0.

Change-Id: If3cb97ff798b22a5fb4e89c0be948ca6b65ee1d1
Changed all qt4 macros to qt5

Change-Id: I597baeeca4bb64f17e4a3682715aca1983f1473e
Obsoleted methods from QHeaderView

Replaced all instances:
QHeaderView::setClickable --> QHeaderView::setSectionsClickable
QHeaderView::setResizeMode --> QHeaderView::setSectionResizeMode
QHeaderView::setMovable --> QHeaderView::setSectionsMovable

Change-Id: I6e583e322db1ebc902d6c86da284f4eef6e36dce
Qt5 obsoletes global typedef qInstallMsgHandler and QtMsgHandler

Using qInstallMessageHander and QtMessageHandler
QtMessageHandler has a different signature than QtMsgHandler providing
information about context. Incorporated that information in the vtkOutputWindow
message printout.

Change-Id: I2c0b9fac88ee2dd28b08d1108654b1983fb7b0fe
QAbstractItemModel::reset() and QAbstractItemModel::createIndex

QAbstractItemModel::reset -
The deprecated function emitted two signals, namely modelAboutToBeReset and
modelReset. Using beginResetModel and endResetModel to emit these signals
instead.

QAbstractItemModel::createIndex -
Ambiguity when compiling with gcc.
When the last parameter is either NULL or 0, GCC fails to resolve
which path to follow. Use the default value (void* ptr = 0) provided in the
function declaration.

Change-Id: I6df26e314bbff6522dab8cd48d328b8b065d91b8
Compile flags (-fPIE) for position independent code

Qt5 is built and packaged with the -reduce-relocations configure option as
default. This causes compilations to run with the -Bsymbolic-functions option,
which makes function pointer comparison ineffective, unless the -fPIE flag is
also supplied.

Change-Id: I61d13993e0cc6fee2e38e8a124e32459f6203d40
Qt5 obsoletes toAscii and fromAscii methods

Replaced all instances:
QString::toAscii --> QString::toLatin1
QString::fromAscii --> QString::fromLatin1
QChar::fromAscii --> QLatin1Char

Change-Id: Ic4f9c5316c73a305ded835e02fc3ff6babffdf39
Multiple Qt5 related minor changes

1. QCursor constructor needs QPixmap instead of const char*
2. Qt::WFlags obsoleted. Replaced by Qt::WindowFlags
3. QPixmap::serialNumber() deprecated. Replaced by QPixmap::cacheKey()
4. QVariant(Qt::GlobalColor) is now private. Use QVariant(QColor(Qt::GlobalColor)) instead.
5. QMetaMethod::signature obsoleted. Replaced by QMetaMethod::methodSignature().
   To avoid runtime issues get the pointer to data using methodSignature().constData()
6. QDir::convertSeparators obsoleted. Replaced by
   toNativeSeparators/fromNativeSeparators
7. QRegion::unite deprecated. Replaced by QRegion::united
8. QCoreApplication::UnicodeUTF8 is deprecated.
9. Missing includes

Change-Id: I44861d866aa2b2b5cb339b620c120a0c075ffd55
Obsoleted constructor for QGraphicsItem

Removed the use of QGraphicsScene from the constructor argument.

Change-Id: I696417dc65db7b978ab35ae07a8f4d4e5b18c640
QtGui library -> include QtGui/* files directly

Change-Id: If348023b9caec26b63c69e257516fb89d494ec08
QWindowsStyle and QPlastiqueStyle obsoleted

Replaced with the Fusion style and the new QStyleFactory::create() API.
Use style depending on Qt version used

Change-Id: Icc89344182f76c07af93600308afac7762ff52ed
Modified plugins to use Qt4 or Qt5 depending on the global configuration

Change-Id: I104bcf927c74c5f84b975f8d5c0df9f3964a9064
Use the new Qt5 plugin architecture

Q_EXPORT_PLUGIN2 deprecated. Replaced by Q_PLUGIN_METADATA
Find the Qt5 RCC executable to generate qrc_* files.

Change-Id: I86e6664e85015e3817d80d5dad1b04deeffe1459
Updated QtTesting to use Qt5

QtTesting should use user selected Qt version
Change-Id: I22337268e9864b5fe2153309f6844cdf3ab4e4b3
Modified ParaView macros to use both Qt4 and Qt5

Depending on the PARAVIEW_QT_VERSION variable value, the appropriate Qt version
is used.
Change-Id: I595069f00809082e30770e0c3e2dcd14ef8f69ae
Import Qt5Widgets module at the top level

This ensures all the required Qt5 variables can be found.
For example, just importing Qt5Core does not help find QT_UIC_EXECUTABLE using
the macro "get_target_property(QT_UIC_EXECUTABLE Qt5::uic LOCATION)". This must
be a Qt5 bug.

Change-Id: Ie6f4a708682ad8cf2391d218c193d8127e4c44f7