Swap tile id map with an unordered map for faster lookup.
Change the season lookup logic to modify the id string and continue instead of calling itself with a new argument.
Misc style cleanup.
Merging my own branch, which is bad form, but we simply don't have anyone else to test it.

* dda/pr/9908:
  Misc style cleanup.
  Change the season lookup logic to modify the id string and continue instead of calling itself with a new argument.
  Swap tile id map with an unordered map for faster lookup.
Fixes the @ screen threshold title.  Looks like the vector wasn't getting populated.
Merge remote-tracking branch 'dda/pr/10060' into dda-master

* dda/pr/10060:
  Fixes the @ screen threshold title.  Looks like the vector wasn't getting populated.
Style cleanup and early loop exit.