America/Cancun switches to EST without DST on 2015-02-01.

* northamerica (America/Cancun): Switch to EST without DST on
2015-02-01 at 02:00.
* zone.tab, zone1970.tab: Update description for America/Cancun.
* NEWS: Document this.

NEWS

@@ -7,6 +7,10 @@ Unreleased, experimental changes
     New leap second 2015-06-30 23:59:60 UTC as per IERS Bulletin C 49.
     (Thanks to Tim Parenti.)
 
+    The Mexican state of Quintana Roo, represented by America/Cancun,
+    will shift from Central Time with DST to Eastern Time without DST
+    on 2015-02-01 at 02:00.  (Thanks to Steffen Thorsen and Gwillim Law.)
+
   Changes affecting past time stamps
 
     Iceland observed DST in 1919 and 1921, and its 1939 fallback

northamerica

@@ -2297,6 +2297,24 @@ Zone America/Dawson	-9:17:40 -	LMT	1900 Aug 20
 # efecto desde las dos horas del segundo domingo de marzo y concluirá a
 # las dos horas del primer domingo de noviembre.
 
+# From Steffen Thorsen (2014-12-08), translated by Gwillim Law:
+# The Mexican state of Quintana Roo will likely change to EST in 2015.
+#
+# http://www.unioncancun.mx/articulo/2014/12/04/medio-ambiente/congreso-aprueba-una-hora-mas-de-sol-en-qroo
+# "With this change, the time conflict that has existed between the municipios
+# of Quintana Roo and the municipio of Felipe Carrillo Puerto may come to an
+# end. The latter declared itself in rebellion 15 years ago when a time change
+# was initiated in Mexico, and since then it has refused to change its time
+# zone along with the rest of the country."
+#
+# From Steffen Thorsen (2015-01-14), translated by Gwillim Law:
+# http://sipse.com/novedades/confirman-aplicacion-de-nueva-zona-horaria-para-quintana-roo-132331.html
+# "...the new time zone will come into effect at two o'clock on the first Sunday
+# of February, when we will have to advance the clock one hour from its current
+# time..."
+#
+# Also, the new zone will not use DST.
+
 # Rule	NAME	FROM	TO	TYPE	IN	ON	AT	SAVE	LETTER/S
 Rule	Mexico	1939	only	-	Feb	5	0:00	1:00	D
 Rule	Mexico	1939	only	-	Jun	25	0:00	0	S
@@ -2317,7 +2335,8 @@ Rule	Mexico	2002	max	-	Oct	lastSun	2:00	0	S
 Zone America/Cancun	-5:47:04 -	LMT	1922 Jan  1  0:12:56
 			-6:00	-	CST	1981 Dec 23
 			-5:00	Mexico	E%sT	1998 Aug  2  2:00
-			-6:00	Mexico	C%sT
+			-6:00	Mexico	C%sT	2015 Feb  1  2:00
+			-5:00	-	EST
 # Campeche, Yucatán; represented by Mérida
 Zone America/Merida	-5:58:28 -	LMT	1922 Jan  1  0:01:32
 			-6:00	-	CST	1981 Dec 23

zone.tab

@@ -274,7 +274,7 @@ MU	-2010+05730	Indian/Mauritius
 MV	+0410+07330	Indian/Maldives
 MW	-1547+03500	Africa/Blantyre
 MX	+1924-09909	America/Mexico_City	Central Time - most locations
-MX	+2105-08646	America/Cancun	Central Time - Quintana Roo
+MX	+2105-08646	America/Cancun	Eastern Standard Time - Quintana Roo
 MX	+2058-08937	America/Merida	Central Time - Campeche, Yucatan
 MX	+2540-10019	America/Monterrey	Mexican Central Time - Coahuila, Durango, Nuevo Leon, Tamaulipas away from US border
 MX	+2550-09730	America/Matamoros	US Central Time - Coahuila, Durango, Nuevo Leon, Tamaulipas near US border

zone1970.tab

@@ -233,7 +233,7 @@ MT	+3554+01431	Europe/Malta
 MU	-2010+05730	Indian/Mauritius
 MV	+0410+07330	Indian/Maldives
 MX	+1924-09909	America/Mexico_City	Central Time - most locations
-MX	+2105-08646	America/Cancun	Central Time - Quintana Roo
+MX	+2105-08646	America/Cancun	Eastern Standard Time - Quintana Roo
 MX	+2058-08937	America/Merida	Central Time - Campeche, Yucatán
 MX	+2540-10019	America/Monterrey	Mexican Central Time - Coahuila, Durango, Nuevo León, Tamaulipas away from US border
 MX	+2550-09730	America/Matamoros	US Central Time - Coahuila, Durango, Nuevo León, Tamaulipas near US border