RFC: Add an API to safely add conda packages #613
  Add this suggestion to a batch that can be applied as a single commit.
  This suggestion is invalid because no changes were made to the code.
  Suggestions cannot be applied while the pull request is closed.
  Suggestions cannot be applied while viewing a subset of changes.
  Only one suggestion per line can be applied in a batch.
  Add this suggestion to a batch that can be applied as a single commit.
  Applying suggestions on deleted lines is not supported.
  You must change the existing code in this line in order to create a valid suggestion.
  Outdated suggestions cannot be applied.
  This suggestion has been applied or marked resolved.
  Suggestions cannot be applied from pending reviews.
  Suggestions cannot be applied on multi-line comments.
  Suggestions cannot be applied while the pull request is queued to merge.
  Suggestion cannot be applied right now. Please check back later.
  
    
  
    
If a package installed via
Conda.addis not available for installedPython version,
condamay downgrade Python:https://discourse.julialang.org/t/help-understanding-pycall-related-travis-failure/15957
This breaks PyCall because it stores the path to libpython etc. This patch provides a workaround to the issue by adding an API that wraps
Conda.addand re-build PyCall if Python version is changed during installation of conda packages. I suggest to recommend this API overpyimport_conda.Proposed API:
fix JuliaPy/Conda.jl#127
fix JuliaPy/PyPlot.jl#382