#14380: Have MIMEText defaults to utf-8 when passed non-ASCII unicode

Previously it would just accept the unicode, which would wind up as unicode in
the transfer-encoded message object, which is just wrong.

Patch by Jeff Knupp.
diff --git a/Misc/ACKS b/Misc/ACKS
index 9ed148e..4e6597d 100644
--- a/Misc/ACKS
+++ b/Misc/ACKS
@@ -548,6 +548,7 @@
 Kim Knapp
 Lenny Kneler
 Pat Knight
+Jeff Knupp
 Greg Kochanski
 Damon Kohler
 Marko Kohtala
diff --git a/Misc/NEWS b/Misc/NEWS
index 02bafcd..b6d7dad 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -34,6 +34,9 @@
 Library
 -------
 
+- Issue #14380: MIMEText now defaults to utf-8 when passed non-ASCII unicode
+  with no charset specified.
+
 - Issue #10340: asyncore - properly handle EINVAL in dispatcher constructor on
   OSX; avoid to call handle_connect in case of a disconnected socket which
   was not meant to connect.