bpo-26707: Enable plistlib to read UID keys. (GH-12153)

Plistlib currently throws an exception when asked to decode a valid
.plist file that was generated by Apple's NSKeyedArchiver. Specifically,
this is caused by a byte 0x80 (signifying a UID) not being understood.

This fixes the problem by enabling the binary plist reader and writer
to read and write plistlib.UID objects.
diff --git a/Misc/ACKS b/Misc/ACKS
index ec5b017..f5a31a8 100644
--- a/Misc/ACKS
+++ b/Misc/ACKS
@@ -754,6 +754,7 @@
 Jack Jansen
 Hans-Peter Jansen
 Bill Janssen
+Jon Janzen
 Thomas Jarosch
 Juhana Jauhiainen
 Rajagopalasarma Jayakrishnan
diff --git a/Misc/NEWS.d/next/Library/2019-03-04-01-28-33.bpo-26707.QY4kRZ.rst b/Misc/NEWS.d/next/Library/2019-03-04-01-28-33.bpo-26707.QY4kRZ.rst
new file mode 100644
index 0000000..ab76540
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2019-03-04-01-28-33.bpo-26707.QY4kRZ.rst
@@ -0,0 +1 @@
+Enable plistlib to read and write binary plist files that were created as a KeyedArchive file. Specifically, this allows the plistlib to process 0x80 tokens as UID objects.
\ No newline at end of file