Post #1352464

@moss I wrote up this comparison document a while ago with text documents as first priority, so most of the headers aren't filled in for slides/presentations, but if they're present they're at least offered by the software in question. Top-level details should indicate whether they're free and whether they have collaboration/sharing functionality. https://docs.google.com/document/d/1O3QsPC_oo3FzT267CrD9ozA7IsscsEqQfkDmzTI2emc/edit?usp=sharing