Merge pull request matplotlib#4922 from tacaswell/doc_qt5

DOC: update qt related prose

Author: WeatherGod

doc/faq/usage_faq.rst

@@ -430,7 +430,8 @@ WXAgg          Agg rendering to to a :term:`wxWidgets` canvas
 WX             Native :term:`wxWidgets` drawing to a :term:`wxWidgets` Canvas
                (not recommended) (requires wxPython_)
 TkAgg          Agg rendering to a :term:`Tk` canvas (requires TkInter_)
-Qt4Agg         Agg rendering to a :term:`Qt4` canvas (requires PyQt4_)
+Qt4Agg         Agg rendering to a :term:`Qt4` canvas (requires PyQt4_ or ``pyside``)
+Qt5Agg         Agg rendering in a :term:`Qt5` canvas (requires PyQt5_)
 macosx         Cocoa rendering in OSX windows
                (presently lacks blocking show() behavior when matplotlib
                is in non-interactive mode)
@@ -448,6 +449,7 @@ macosx         Cocoa rendering in OSX windows
 .. _wxPython: http://www.wxpython.org/
 .. _TkInter: http://wiki.python.org/moin/TkInter
 .. _PyQt4: http://www.riverbankcomputing.co.uk/software/pyqt/intro
+.. _PyQt5: http://www.riverbankcomputing.co.uk/software/pyqt/intro
 
 How do I select PyQt4 or PySide?
 ========================================

doc/glossary/index.rst

@@ -73,9 +73,9 @@ Glossary
   pyqt
       `pyqt <http://wiki.python.org/moin/PyQt>`_ provides python
       wrappers for the :term:`Qt` widgets library and is required by
-      the matplotlib QtAgg and Qt4Agg backends.  Widely used on linux
+      the matplotlib Qt5Agg and Qt4Agg backends.  Widely used on linux
       and windows; many linux distributions package this as
-      'python-qt3' or 'python-qt4'.
+      'python-qt5' or 'python-qt4'.
 
   python
       `python <http://python.org>`_ is an object oriented interpreted
@@ -91,13 +91,18 @@ Glossary
 
 
   Qt
-      `Qt <http://trolltech.com/products/qt/>`__ is a cross-platform
+      `Qt <http://www.qt.io/>`__ is a cross-platform
       application framework for desktop and embedded development.
 
   Qt4
-      `Qt4 <http://trolltech.com/products/qt/>`__ is the most recent
-      version of Qt cross-platform application framework for desktop
-      and embedded development.
+      `Qt4 <http://doc.qt.io/qt-4.8/index.html>`__ is the previous,
+      but most widely used, version of Qt cross-platform application
+      framework for desktop and embedded development.
+
+  Qt5
+      `Qt5 <http://doc.qt.io/qt-5/index.html>`__ is the current
+      version of Qt cross-platform application
+      framework for desktop and embedded development.
 
   raster graphics
       `Raster graphics