DOC: fix download link for Anaconda Python

Author: pavoljuhas

README.rst

@@ -34,7 +34,7 @@ that are used by PDFgui and its components.
 * diffpy.utils - shared helper utilities for wx GUI,
   https://github.com/diffpy/diffpy.utils
 
-We recommend to use `Anaconda Python <https://www.continuum.io/downloads>`_
+We recommend to use `Anaconda Python <https://www.anaconda.com/download>`_
 which allows to conveniently install PDFgui and all its software
 dependencies with a single command.  For other Python distributions
 it is necessary to install the required software separately.  As an

doc/manual/pdfgui.html

@@ -302,7 +302,7 @@ easier to distribute software updates and also results in the same
 installation procedure on all supported platforms.
 
 To install PDFgui, download and install Anaconda for Python 2.7 from
-@url{https://www.continuum.io/downloads}.  When ready open a terminal
+@url{https://www.anaconda.com/download}.  When ready open a terminal
 application (or @i{Anaconda Command Prompt} on Windows) and use the
 @command{conda} package manager to install PDFgui from the ``diffpy''
 channel of Anaconda packages