Version per distro

ROS 1

ROS 1 distros use major version 2. The minor is usually bumped for each new distro.

ROS 2 distros use major version 3. The minor is usually bumped for each new distro.

Distro	Versions	Branch
Crystal	3.2.x	`crystal`
Dashing	3.3.x	`dashing`
Eloquent	3.4.x	`eloquent`
Foxy	3.5.x	`foxy` (note: 3.5.1 and 3.5.2 were wrongly released for Rolling)
Galactic	3.6.x	`galactic` (note: 3.6.0 were wrongly released for Rolling)
Humble (current Rolling)	3.7.x	`ros2` (for now)