Adds simple string / integer concatenation functions.
Many of the uses of `fmt::format` are simply concatenation
of a few strings and integers.
`StrCat` is an easier-to-read alternative to such uses of `fmt`.
1. Do not modify the map after loading. Instead, return string views
(guaranteed to be null-terminated) from look up functions and return
the key directly if not found.
2. Use an `unorded_map` instead of `map` where available (C++20).
Saves a bit of RAM (~50 KiB) and improves lookup performance.
Gleb Mazovetskiy
obligaron
Anders Jenbo
Jonathan Mercier-Ganady
Jmgr