[Feature request] handling of UTF-16 and UTF-32 encoding

[ohault]

In follow-up of https://github.com/dbohdan/initool/issues/15, a level of support of UTF-16 LE encoding will be desired.

A very first level, would be to recognize a file encoded in either UTF-16 or UTF-32 and to handle a specific error to instruct/advice the user to convert input file into a encoding supported by initool.

In inicomp tool, an error message is displayed with an instruction for the user. "Error: File .................. is encoded as UTF16. Please convert it to ANSI or UTF8 first."