Mermaid refresh

I know mermaids would be better with a proper skill tree but given that we'll not get one, we could have little things to make them work better than they do now.

FEEDBACK:

• [City Living] Make mermaids have high initial singing skill (How can they sing that way and not have any?);

• [Seasons] Stop mermaids getting uncomfortable/frozing to death from swimming in cool temperature;

• [Seasons] Stop mermaids being scared of thunderstorms (They can literally control it);

• Ability to ghost mermaids to be on mermaid form and have the swimming animation as walkstyle;

• Stop mermaids always going to bodies of water (keep it to low/medium hydration);

• Stop "Pulled muscle" from swimming (They're built for that);

SUGGESTIONS:

• Turn the hydration need in a special bar like vampire energy bar (since they work similarly);

• Add "Underwater travel" interaction (similar to Tunneler werewolves): They should be able to travel quickly on water bodies knowing underwater tunnels;

• Add "Underwater food hunting" interaction (similar to Hunter werewolves): Living on water should be totally self sufficient for them.