time: format stdNumShortTZ not working

[requilence]

Here is the example:
http://play.golang.org/p/aQzzsC_ZS6

stdNumShortTZ is missed in the case switch:

go/src/time/format.go

Line 540 in f4b4d2f

case stdISO8601TZ, stdISO8601ColonTZ, stdISO8601SecondsTZ, stdISO8601ColonSecondsTZ, stdNumTZ, stdNumColonTZ, stdNumSecondsTz, stdNumColonSecondsTZ:

Also there is a need to check for stdNumShortTZ before appending minutes here:

go/src/time/format.go

Line 556 in f4b4d2f

b = appendInt(b, zone/60, 2)

[gopherbot]

CL https://golang.org/cl/17260 mentions this issue.