Tournament pages

Some minor corrections and improvements on the tournament pages:
- display of the computers allowed/forbidden icons
- correction of the tournament info of swiss tournaments
- changed the sort order of the tournament table for incomplete rounds
- latest results in swiss tournaments (PCO)

The newest 3 blog entries are shown on the player homepages. This replaces the older anouncements section there. These new technique has several advantages:
- entries older than 7 days are automatically removed
- only the first few words of the message are displayed. This avoids cluttering your player homepage
- these blog messages are automatically archived for later investigations