Deathlink message standardisation

[soreikomori]

Currently deathlink messages are either flavoured:

Deathlink: The final flash seen by PLAYER.

Or have a cause:

**Deathlink received from: PLAYER**
Cause: PLAYER took damage equal to or more than their current HP.

So the flavour deathlink texts are completely unused and pretty much irrelevant if the game provides a cause.

This pull request changes the deathlink messages a little so that the flavour is always used independently of the cause:

# Flavoured:
**Deathlink!** Bad timing ended **PLAYER**.
*Cause:* PLAYER took a long nap.

# Non-flavoured:
**Deathlink!** Received from **PLAYER**.
*Cause:* PLAYER took a long nap.