Bump version number (Synergy, 302a419)

Created 7/20/2007, updated 3/5/2024

snippets

Distinguish this (the Leopard branch) from ongoing Jaguar/Panther/Tiger development by bumping the version number to "3.5-pre"; the final release for Leopard will eventually be version 3.5.

Signed-off-by: Greg Hurrell <greg@hurrell.net>