DOC: fix download link for Anaconda Python

Author: pavoljuhas

README.rst

@@ -32,7 +32,7 @@ The diffpy.Structure requires Python 2.7 and the following software:
 * ``setuptools`` - software distribution tools for Python
 * ``NumPy`` - numerical mathematics and fast array operations for Python
 
-We recommend to use `Anaconda Python <https://www.continuum.io/downloads>`_
+We recommend to use `Anaconda Python <https://www.anaconda.com/download>`_
 as it allows to install all software dependencies together with
 diffpy.Structure.  For other Python distributions it is necessary to
 install the required software separately.  As an example on Ubuntu