Add a note that package names need to be lowercase
Add a note that package names need to be lowercase

I am not going to call .lower() here because it is again up to the package
authors to take care of sanitization for bdist_conda.

rmcgibbo/conda-build,mwcraig/conda-build,rmcgibbo/conda-build,takluyver/conda-build,frol/conda-build,frol/conda-build,sandhujasmine/conda-build,dan-blanchard/conda-build,mwcraig/conda-build,shastings517/conda-build,takluyver/conda-build,dan-blanchard/conda-build,takluyver/conda-build,ilastik/conda-build,rmcgibbo/conda-build,shastings517/conda-build,sandhujasmine/conda-build,frol/conda-build,dan-blanchard/conda-build,sandhujasmine/conda-build,ilastik/conda-build,mwcraig/conda-build,shastings517/conda-build,ilastik/conda-build