Time presentation: default display time as 24-hour in zero-prefixed mono-space font

[sladen]

Presently times are displayed using a 12-hour times post-fixed by 'AM/PM', without zero prefixing, and in a proportional font. This means that the time '1:11 PM' is a different width to '12:00 AM', resulting in the time waving back and forth. The space occupied by ' AM' or ' PM' takes up 30-40% of the total space for the timestamp. A possible solution would be one, or all of the following:

1. Zero-prefixing (6:00 PM becomes 06:00 PM); this creates an equal number of characters for all timestamps
2. Mono-space font (06:00 PM becomes 06:00 PM); this creates an equal pixel width for all timestamps
3. 24-hour (06:00 PM becomes 18:00); this saves 38% of the width of the monospace timestamp by removing three characters