Add !rand, !brickcolors, !materials, updated !usage

[Expertcoderz]

- Random number generation

• !rand - a real number between 0 and 1
• !rand <upper> - an integer between 1 and <upper> (both inclusive)
• !rand <lower> <upper> - an integer between <lower> and <upper> (both inclusive)

- BrickColors reference list:

!brickcolors (sorted alphabetically)

- Materials reference list:

!materials

- Updated !usage information

[coasterteam]

There's a much better way to get all brick colors, no need to list them all.
BrickColor.palette()
https://developer.roblox.com/en-us/api-reference/datatype/BrickColor

[Expertcoderz]

There's a much better way to get all brick colors, no need to list them all.
BrickColor.palette()
https://developer.roblox.com/en-us/api-reference/datatype/BrickColor

Fixed. I should have known earlier. Thanks!

[LolloDev5123]

Ah yes I approve these changes [imagine this is a thumbsup]