Bugfix: Shield Egos and Powers on Steamsaws

[helminthauge]

To fix the bug "Steamsaw Stats Not Showing in the Character Sheet" as reported in http://forums.te4.org/viewtopic.php?f=42&t=49898, with https://te4.org/games/addons/tome/shiel ... w%20bugfix, when you try to equip a steamsaw, its special_combat field will be removed and the APR bonus, block bonus, weapon damage bonus, critical chance bonus, melee project, burst on hit/crit, and special effects on hit/crit in special_combat field will be added to combat field, plus if there was a special damage type in special_combat field and the damage type in combat field is physical bleed, the damage type will be overrided.

Why I choose to change the item stats on when one try to equip it instead of on its generation is that I cannot really understant how items are created in this game, so I'm leaving it to the devs.