Initialize some char arrays to empty.
Playlist Event code cleanup and fixes.

- Display event ID and name in playlist editor and list.
- Spawn scripts from the scripts directory.
- Add a drop-down for the script name in the event editor instead of
  using a fre-form text input field.
Playlist editor fix

- Adding a pause entry was showing the video delay text header.
Add missing video.c and video.h files for playing video in playlists.