Give Water Domain more watery benefits

[sirTouchington]

Water domain is fairly lackluster compared to others. The spells it gets aren't nearly as good, it has one of the weaker summoning themes, and it's turn undead isn't really that useful.

It would be neat to see it get more benefits for underwater stuff! Underwater breathing boost, bonus for swimming, or less spellfail underwater would be a nice buff to one of the weaker primary domains.