Better alarm indicators

[shape-warrior-t]

In the Astra mockups, alarms have associated colours based on their priority and new alarms are bolded. Neither the colour nor the bolding is present in the current version of Astra.

Treeviews in Tkinter (which are currently used for tables) do not support changing the colour of a single cell, so replicating the mockups here will require either a workaround of some kind or a rewrite to create tables in some other fashion.