Support the glossaries package

[davidmjones]

We occasionally get publications that use the glossaries package. Currently we just drop the glossaries, but we should figure out how to support them somehow.

Some affected documents:

• https://github.com/AmerMathSoc/memo/issues/64
• https://github.com/AmerMathSoc/memo/issues/54

[pkra]

Is this different from #160?