feat(data): add skill cost, item vnum, dash, upgrade

feat(data): add skill attack type, uses secondary weapon and element

Merge pull request #32 from Rutherther/combat

Add combat extension

chore(data): add cast time and cooldown units to documentation

Merge pull request #22 from Rutherther/data

Add NosTale data information

feat(data): add correct information into infos

feat(data): add skeleton for NosTale data