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[ethanwhite]

In the section on r2u include a note on forcing bspm to only use apt binaries to avoid failures in the gap between when packages with external Linux deps get updated and when the updates are available on r2u. See:

https://github.com/weecology/dcsem-solutions/commit/8c6a9684930bc69e8b014489887f407a94d0bc84