Proposed schedule for JavaFX 20

[Kevin Rushforth]

Here is the proposed schedule for JavaFX 20.

RDP1: Jan 12, 2023 (aka “feature freeze”)
RDP2: Feb 2, 2023
Freeze: March 2, 2023
GA: March 21, 2023
We plan to fork a jfx20 stabilization branch at RDP1.

The start of RDP1, the start of RDP2, and the code freeze will be 16:00 
UTC on the respective dates.

Please let Johan or me know if you have any questions.

-- Kevin