Change description of time.Time.ZoneOffset to specify east is +ve.

Currently, the description says that +ve numbers are westwards of UTC.
Typically, timezones are specified with +ve numbers running east of Greenwich.
For example, San Francisco is specified as UTC-8. Also, when calling
time.Localtime(), the following is returned on my box in PDT:

{Year:2009 Month:10 Day:5 Hour:18 Minute:55 Second:6 Weekday:1 ZoneOffset:-25200
Zone:PDT}

Note that the ZoneOffset is negative. This leads me to suspect that the
description is mistaken.

R=rsc
APPROVED=rsc
DELTA=1  (0 added, 0 deleted, 1 changed)
OCL=35356
CL=35377

src/pkg/time/time.go

@@ -47,7 +47,7 @@ type Time struct {
 	Month, Day int;	// Sep-17 is 9, 17
 	Hour, Minute, Second int;	// 10:43:12 is 10, 43, 12
 	Weekday int;		// Sunday, Monday, ...
-	ZoneOffset int;	// seconds west of UTC
+	ZoneOffset int;	// seconds east of UTC
 	Zone string;
 }