Fix dependency management issue for remarks

[shaunagm]

One of the REMARKs uses a different version of HARK than the others. Currently Chris has scotch-taped his way around this by pasting the alternate code directly into the Jupyter notebook, but that's not ideal.

I talked to Carol Willing (a Jupyter expert) who suggested one workaround is to import from a different release at the beginning of the notebook, which is slightly easier.

[shaunagm]

Okay, this is now no longer blocked by our release system. @llorracc, you can try removing all that extra code in the Bufferstock notebook and replacing !pip install econ-ark with !pip install econ-ark==0.10.0.dev1 (or, if you're checking via mybinder rather than colab, by making a similar change in the binder requirements file).

[shaunagm]

According to @llorracc, this works now, so I'm closing.