#2020 recommend utf-8 in locale.properties, and add missing =

[Ben Fisher]

A few small suggestions for locale.properties.

Add missing = character. Recommend UTF-8 for new translations (Unicode support is now widespread and use of other encodings is rare, two people have contacted me/opened a GitHub issue to suggest this).

Move TranslationCredit to the top of the file; many translations had not updated it correctly. (Most updates to a translation updated author information at the top of the file but didn't update the TranslationCredit line, and a handful of files translated literally the words "translation credit".)

[Neil Hodgson]

OK, committed as [3b8358] with a small change to the comment.

[Ben Fisher]

Thank you,
-Ben