This connects Xterm.js to a Nomad exec websocket so people
can interact on clients via live sessions. There are buttons on
job, allocation, task group, and task detail pages that open a
popup that lets them edit their shell command and start a
session.
More is to come, as recorded in issues.
By default, blocks have a margin of 1.5em to create a consistent
vertical rhythm. However, sometimes elements need to be associated with
the element above them. In this cases, the gap between elements needs to
be tighter. There are many ways to do this, but this approach asks the
latter content to be marked as associative. The implication is that the
association is with the previous block.
