[robocup-humanoid] Soccer ball for this year

[Ludovic Hofer]

Dear RoboCuppers,

This year we expect to play with the following balls:

  * Adult and Teen:
    https://www.rebelsport.com.au/p/adidas-telstar-2018-top-glider-soccer-ball-M54542101.html
  * Kid: https://www.ballsports.com.au/adidas-world-cup-mini-soccer-ball

See you in Sydney,

Ludovic Hofer