skpkg: `README.rst` missing a `conda install` line

[tinatn29]

Problem

README.rst auto-generated by scikit-package is missing a conda install line.

We want to install our packages in a suitable conda environment.
The following creates and activates a new environment named diffpy.fourigui_env ::

    conda create -n diffpy.fourigui_env diffpy.fourigui
    conda activate diffpy.fourigui_env

To confirm that the installation was successful, type ::

    python -c "import diffpy.fourigui; print(diffpy.fourigui.__version__)"

Proposed solution

Edit README.rst (and scikit-package?) to add these lines between conda activate ... and "To confirm that the installation was successful..."

Then, to fully install fourigui in our active environment, run ::

    conda install fourigui

[tinatn29]

@sbillinge @cadenmyers13 I notice that the Installation section on README.rst generated by scikit-package is missing a conda install step (it goes directly from conda activate <conda environement> to checking if the installation was successful.

I could manually edit README.rst here, but we should also fix this in scikit-package?

[sbillinge]

@tinatn29 did you test the commands? If the package requirements are correctly listed in the package release then the conda create -n diffpy.fourigui_env diffpy.fourigui should install diffpy.fourigui and all its dependencies in that env so there is no need for a subsequent conda install step.