Change Worldstone shard drop rate

1. Equalize Worldstone shard drop rate

Changes the worldstone shard drop rates that by default heavily favor act 1 shards in mid to late game.

This does not change the overall chance to find a worldstone shard. It only equalizes their distribution.

2. Shard multipliers

Adds a multiplier for every shard, so it is possible to increase the drop rate for certain shards or boost all of them.

3. Cube recipes

Adds cube recipes to combine any two shards into a new one.

The new shard act will be the sum of the ingredients (modulo 5):

Act 1 + Act 1 -> Act 2

Act 1 + Act 2 -> Act 3

Act 1 + Act 3 -> Act 4

Act 1 + Act 4 -> Act 5

Act 2 + Act 2 -> Act 4

Act 2 + Act 3 -> Act 5

Act 2 + Act 4 -> Act 1

Act 3 + Act 3 -> Act 1

Act 3 + Act 4 -> Act 2

Act 4 + Act 4 -> Act 3

There are no recipies using Act 5 shards because the result would always be the same as the other ingredient.

(e.g. Act 1 + Act 5 -> Act 1)