Remove Canna from Haiku source tree
|Reported by:||luroh||Owned by:|
Since hrev47632, Canna is available as an optional package from HaikuPorts (haikuports/app-i18n/canna).
Note that the HaikuPorts recipe uses sources on GitHub which lack any Haiku commit history, since it was copied as a one-off snapshot. Not sure if there is a way around this, or if it's even worth looking into.