travel: added cpsk bus and train info

Signed-off-by: Adrian Matejov <a.matejov@centrum.sk>

update: dict variable and removed str

* message is now being get from event.meta['body']
* date is no longer being retyped to str

Signed-off-by: Adrian Matejov <a.matejov@centrum.sk>

requirements: added cpsk

Signed-off-by: Adrian Matejov <a.matejov@centrum.sk>

travel: added cmds for bus and train in cpsk

Signed-off-by: Adrian Matejov <a.matejov@centrum.sk>
travel: cpsk plugin

* searches for bus/train lines in Slovakia
* ability to match query or use cmds !bus or !vlak
* time and date specification feature

Signed-off-by: Adrian Matejov <a.matejov@centrum.sk>