Add a Meetings block (for WP block themes)

[joshreisner]

Add a block called "Meetings" to enable block theme editors to embed TSML UI directly.

[joshreisner]

looks like TSML Xtras has almost exactly what we want here. i would recommend titling the block (in the list and on the page) as "Meetings" and instead of the "Some blocks will not render" text say something like "View the page to see the block. it's recommended not to put any page content below the block, and to make the block as wide as possible."

Also there is a PHP warning that might be looked into and it might need a div wrapper with 1rem of horizontal padding