Include alloca header if needed

Signed-off-by: Claudio Matsuoka <cmatsuoka@gmail.com>
Improve OctaMED effect handling

Implement most of previously ignored OctaMED effects. Reported by
Andreas Falkenhahn <andreas@falkenhahn.com>.

Signed-off-by: Claudio Matsuoka <cmatsuoka@gmail.com>
Update changelog

Signed-off-by: Claudio Matsuoka <cmatsuoka@gmail.com>
Update version number

Signed-off-by: Claudio Matsuoka <cmatsuoka@gmail.com>