Make resolve strategies configurable

[Jannyboy11]

InvSee++'s config should contain a section in which server admins can configure the default resolve strategy order for player Unique IDs and UserNames. I imagine this would look something like this:

# Configure the order of strategies used in order to obtain Unique IDs for provided usernames.
# Possible values: "online player", "logged out players cache", "paper offline player cache", "permission plugin", "proxy", "mojang rest api call", "electroid mojang api call", "player data save files".
uuid-resolve-strategies:
  - "online player"
  - "logged out players cache"
  - "paper offline player cache"
  - "permission plugin"
  - "proxy"
  - "mojang rest api call"
  - "player data save files"

and similar for username-resolve-strategies.

[Jannyboy11]

We should not forget the most important strategy for servers in offline mode: "spoof".