* Update base `clock`-icons
Replace `<polyline/>`s with `<path/>`s, and adjust the angles of the 2-, 4-, 8- and 10 o'clock hour hands to better match the 1-, 5-, 7- and 11 o'clock hands
* Update clocks with symbols
Update `clock-arrow-down`, `clock-arrow-up` and `clock-alert` to match the hand angle of `clock`
Also align the exclamation mark of `clock-alert` to the pixel grid
* Update small clock faces
Make the clock faces in `calendar-clock`, `file-clock`, `folder-clock` and `watch` consistent with each other, and resolve some two-pixel-gap violations.
* Align the tips of all hours hands on large clocks to the grid
* Add self-attribution where appropriate
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Co-authored-by: Eric Fennis <eric.fennis@gmail.com>
