[Revnpcsys] Revisioned Npc System v1.1

[x] I have followed proper The Forgotten Server code styling.
[x] I have read and understood the contribution guidelines before making this PR.
[x] I am aware that this PR may be closed if the above-mentioned criteria are not fulfilled.

Revisioned Npc System v1.1

npc now correctly clears all npc id data when he is removed
farewell and greet messages can be individually set per talk state if not they fall back to default
fixed a bug if the npc disappeared while the player was talking to him, then the npc would not respond to the player again once he was spawned
better warning/error messages which show which npc it occured and which file it originates from
added shop callback function callback(npc, player, handler, items, afterDiscount) order: discount (if there is any) -> callback
added NpcsHandler:player() this is basicly the equivalent to requirements but instead of requireing you can add/set stuff to the player (modules.lua)
implemented modules they're load after callbacks order: requirements (if returns true) -> callback (if returns true) -> modules
moved teleport/addItems/setStorageValue to modules
added new requirements
changed the requirements functions I've included the error message directly inside the functions
removed :failureRespond & :getFailureRespond as they're redundant with requirement re work
changed modules outfit function it requires to insert 2 different outfits now because of 2 different player sexes ex: :outfit(id1, id2, addon)
a few linter/annotation fixes
if the player changed the talk state but still had the shop open and then tried to purchase something it thrown errors, this is now fixed

Issues addressed:

otland / forgottenserver