[contactsd-birthday-plugin] Fix birthday all day event state

mkcal sqlite backend is crap: it requires times being from midnight
to midnight to get all day events. Might be good idea to fix that
but in the meanwhile better to just create events it expects.
[contactsd-birthday-plugin] remove birthday event cheer for now

Should be better showing birthdays as special case in application side.
Merge pull request #50 from pvuorela/master

adjust birthday details