Update README with conda instructions.

Author: pavoljuhas

README.rst

@@ -38,7 +38,7 @@ http://diffpy.github.io/diffpy.srfit.
 REQUIREMENTS
 ------------------------------------------------------------------------
 
-The diffpy.srfit package requires Python 2.6 or 2.7 and the following software:
+The diffpy.srfit package requires Python 2.7 and the following software:
 
 * ``setuptools`` - software distribution tools for Python
 * ``NumPy`` - numerical mathematics and fast array operations for Python
@@ -63,53 +63,52 @@ sums require
 Optimizations involving small angle scattering or shape characteristic
 functions from the diffpy.srfit.sas module require
 
-* ``sas.pr`` - module for calculation of P(R) in small-angle scattering
+* ``sas`` - module for calculation of P(R) in small-angle scattering
   from the SasView project, http://www.sasview.org
 
-On Ubuntu Linux, the required software can easily be installed using
-the system package manager::
+We recommend to use `Anaconda Python <https://www.continuum.io/downloads>`_
+as it allows to install all software dependencies together with
+diffpy.srfit.  For other Python distributions it is necessary to
+install the required software separately.  As an example, on Ubuntu
+Linux some of the required software can be installed using ::
 
    sudo apt-get install \
       python-setuptools python-numpy python-scipy python-matplotlib
 
-For Mac OS X systems with the MacPorts package manager, the required
-software can be installed with ::
-
-   sudo port install \
-      python27 py27-setuptools py27-numpy py27-scipy py27-matplotlib
-
-When installing for MacPorts, make sure the MacPorts bin directory is the first
-in the system PATH and that python27 is selected as the default Python version
-in MacPorts::
-
-   sudo port select --set python python27
-
 For other required packages see their respective web pages for installation
 instructions.
 
 
 INSTALLATION
 ------------------------------------------------------------------------
 
-The easiest option is to use the latest DiffPy-CMI release bundle from
-http://www.diffpy.org, which comes with diffpy.srfit and all other
-recommended software included.
+The preferred method is to use Anaconda Python and install from the
+"diffpy" channel of Anaconda packages ::
+
+   conda config --add channels diffpy
+   conda install diffpy.srfit
+
+diffpy.srfit is also included in the "diffpy-cmi" collection
+of packages for structure analysis ::
+
+   conda install diffpy-cmi
 
-Or, use ``easy_install`` to download and install the latest release from
-`Python Package Index <https://pypi.python.org>`_ ::
+Another option is to use ``easy_install`` to download and install the
+latest release from `Python Package Index <https://pypi.python.org>`_ ::
 
-   sudo easy_install diffpy.srfit
+   easy_install diffpy.srfit
 
-If you prefer to install from sources, make sure all required software packages
-are in place and then run ::
+If you prefer to install from sources, make sure all required software
+packages are in place and then run ::
 
-   sudo python setup.py install
+   python setup.py install
 
-This installs diffpy.srfit for all users in the default system location.
-If administrator (root) access is not available, see the usage info from
-``python setup.py install --help`` for options to install to user-writable
-directories.  The installation integrity can be verified by changing to
-the HOME directory and running ::
+You may need to use ``sudo`` with system Python so the process is
+allowed to put files to the system directories.  If administrator (root)
+access is not available, consult the output from
+``python setup.py install --help`` for options to install to a
+user-writable locations.  The installation integrity can be verified by
+changing to the HOME directory and running ::
 
    python -m diffpy.srfit.tests.run