Changed approach to generating new puzzles

Changed approach to generating new puzzles. Now they will be generated in advance, but will become available in a single time: at 07 minutes past each hour. And in 37 minutes of each hour from 11:37 at 22:37 on weekdays. Type kivirauma puzzle is randomly selected.
Number activated at once puzzles can range from 0 to 5 depending on the accumulated reserve.

Recall, there is always new puzzles - in tournaments. After each round they become available for all in addition to the above-mentioned puzzles.
#of novolisina