timeBasedSeq creates duplicate values due to DST

[joshuaulrich]

Examples on stackoverflow:

• timeBasedSeq function repeats some of the days it creates!
• Repeated date in R timeBasedSeq

R> Sys.setlocale("LC_TIME", "en_US.UTF-8")
R> timeBasedSeq("1986-10-25/1986-10-27")
[1] "1986-10-25" "1986-10-26" "1986-10-26" "1986-10-27"
R> timeBasedSeq("2010-11-06/2010-11-08/d")
[1] "2010-11-06" "2010-11-07" "2010-11-07" "2010-11-08"

A suggested solution is:

> git diff R/timeBasedSeq.R
diff --git a/R/timeBasedSeq.R b/R/timeBasedSeq.R
index c9b73e7..baa6e14 100644
--- a/R/timeBasedSeq.R
+++ b/R/timeBasedSeq.R
@@ -76,7 +76,7 @@ function(x, retclass=NULL, length.out=NULL) {
   if(max.resolution == 0) 
     max.resolution <- 1

-  resolution <- c('year','month','day','hour','mins','secs')[max.resolution]
+  resolution <- c('year','month','DSTday','hour','mins','secs')[max.resolution]

   if(!is.na(BY)) resolution <- names(match.arg(BY, list(year  ='Y',
                                                         month ='m',