updated readme.rst with conda install guidelines

README.rst

@@ -90,6 +90,8 @@ Install the latest `release <https://anaconda.org/conda-forge/dowhy>`__ using co
 
    conda install -c conda-forge dowhy
 
+If you face "Solving environment" problems with conda, then try :code:`conda update --all` and then install dowhy. If that does not work, then use :code:`conda config --set channel_priority false` and try to install again. If the problem persists, please add your issue `here <https://github.com/microsoft/dowhy/issues/197>`_.
+
 **Development Version**
 
 If you prefer the latest dev version, clone this repository and run the following command from the top-most folder of