Throwing knife won't show dammod from Arcane Might

[starsapphire]

Currently, throwing knife and dream smith class talents will not show the extra damage modifier provided by Arcane Might nor Superpower.
It will make people feel these two prodigy will not work on talent-created weapons, but in fact they actually works just fine, it's just a display error.
Writhing One's Tentacle will display it well, because they use `Object:descCombat` instead of hard-code the damage modifier in talent description.
Use a single general function instead of the old hard coded description in that two trees will fix this bug and reduce duplicate code. Psi combat also shows weapons stats in talents, so it can also be good to intergrate them into one function.