Add flight speed

[Sergittos]

Introduction

This pull request makes it possible for developers to modify a player's flight speed.

Relevant issues

Closes #5155

Changes

API changes

Added the following methods in Player:

• Player->setFlightSpeed(): Sets the player's flight speed.
• Player->getFlightSpeed(): Returns the player's flight speed.

Added the following constant in Player:

• Player::DEFAULT_FLIGHT_SPEED

Tests

https://streamable.com/vctb3y

[dktapps]

My issue with this is the same as the past PRs on the subject. There's no explanation or documentation of what the values mean, or why it's 0.05 by default. What's the unit? Blocks per seconds? Blocks per tick?

There's also going to be questions like why doesn't setMovementSpeed() affect flying speed, and why the server-side flight speed doesn't change when sprint-flying (which is inconsistent with movement speed).

The name setFlightSpeed() would be more in line with functions like setMovementSpeed().

[ShockedPlot7560]

I also think the name isn't quite right. It will indeed be confusing. However, I don't think that the unity problem should hinder the merge of adding APIs. It's up to the developers to find out what they're modifying, and a warning could be added in the docs about this. That the unit is not determined and that the value should be handled with care?

[ShockedPlot7560]

Looks ok to me

[Gaprix]

Why should we disallow setting negative flight speed values? Negative values make the player fly backwards, and this can be used in some game modes