This pull request ended up trying to solve three issues at once, because I kept running into errors in the build process.
Force the flask version to at least 1.1.3, because earlier releases allowed the use of incompatible versions of their dependencies.
Stop building for python 3.6 because it results in build failures and is no longer supported upstream.
Host the GloVe model ourselves. There's no guarantee that Stanford will continue to host an eight-year-old data set in perpetuity, and I'd rather not continue to abuse their hosting by slurping up almost a gigabyte of data for each mindmeld installation (including each unit test run).
This pull request ended up trying to solve three issues at once, because I kept running into errors in the build process.