Support buttons > 5 in translation tables [v2]
Add support for arbitrary button numbers by replacing the table-driven detail parsing for BtnDown/ButtonPress and BtnUp/ButtonRelease with a custom parser that allows for an arbitrary button number (1-255) after the 'Button' prefix. Document what this syntax looks like in the table of detail information. Signed-off-by: Keith Packard <keithp@keithp.com>