Update local leap second file

userspace/rootfs_override/etc/leap-seconds.list

@@ -61,7 +61,12 @@
 #	or
 #		Terry Quinn, "The BIPM and the Accurate Measurement
 #		of Time," Proc. of the IEEE, Vol. 79, pp. 894-905,
-#		July, 1991.
+#		July, 1991. <http://dx.doi.org/10.1109/5.84965>
+#		reprinted in: 
+#		   Christine Hackman and Donald B Sullivan (eds.)
+#		   Time and Frequency Measurement
+#		   American Association of Physics Teachers (1996)
+#		   <http://tf.nist.gov/general/pdf/1168.pdf>, pp. 75-86
 #
 #	4. The decision to insert a leap second into UTC is currently
 #	the responsibility of the International Earth Rotation and
@@ -199,10 +204,10 @@
 #	current -- the update time stamp, the data and the name of the file
 #	will not change.
 #
-#	Updated through IERS Bulletin C52
-#	File expires on:  28 June 2017
+#	Updated through IERS Bulletin C57
+#	File expires on:  28 December 2019
 #
-#@	3707596800
+#@	3786480000
 #
 2272060800	10	# 1 Jan 1972
 2287785600	11	# 1 Jul 1972
@@ -247,4 +252,4 @@
 #	the hash line is also ignored in the
 #	computation.
 #
-#h	dacf2c42 2c4765d6 3c797af8 2cf630eb 699c8c67
+#h 	83c68138 d3650221 07dbbbcd 11fcc859 ced1106a