Code to convert strings from a few common codepages to UTF-8. Loosely based on https://github.com/adamdruppe/misc-stuff-including-D-programming-language-web-stuff/blob/master/characterencodings.d
True if data contains non-ASCII characters.
Replaces non-ASCII characters (with the high bit set) with the Unicode replacement character.
Convert text in an arbitrary (known) encoding to UTF-8.
High part of known 8-bit code pages.