Multiple locales: Add date_fmt (bug 24054)

It is not specified what should be the content of d_t_fmt and date_fmt
but in the built-in C locale those fields have only one difference:
date_fmt contains "%Z" (the current time zone) while d_t_fmt does not.

For most of the locales this commit does the following operation:
copy d_t_fmt to date_fmt, and then remove "%Z" from d_t_fmt.
If "%Z" was originally missing from d_t_fmt add it to date_fmt.
It also corrects comments where necessary.

Exceptions:

* In bo_CN, dz_BT, and km_KH "%Z" has not been added to date_fmt because
  it was too difficult.  In these locales date_fmt has been set to the
  copy of d_t_fmt.
* In en_DK "%Z" has not been removed from d_t_fmt in order to preserve
  the conformance with the standard mentioned in the comment.

The command to identify and initially edit the locales that need the
update was:

    for i in `grep -lw d_t_fmt *`
    do
        if ! grep -qw date_fmt $i ; then
            awk '/d_t_fmt/ { print $0; gsub("d_t_fmt", "date_fmt"); } //{ print $0 }' < $i > $i.next
            mv $i.next $i
        fi
    done

and then each file was further edited manually.

1 files changed, 2 insertions, 1 deletions

diff --git a/localedata/locales/ig_NG b/localedata/locales/ig_NG
index 113294a0f5..7e678b01cd 100644
--- a/localedata/locales/ig_NG
+++ b/localedata/locales/ig_NG
@@ -263,7 +263,8 @@ mon         "Jen<U1EE5>war<U1ECB>";/
             "Novemba";/
             "Disemba"
 % FIXME
-d_t_fmt     "%A, %d %B %Y %T %Z"
+d_t_fmt     "%A, %d %B %Y %T"
+date_fmt    "%A, %d %B %Y %T %Z"
 d_fmt       "%d//%m//%y"
 t_fmt       "%r"
 am_pm       "AM";"PM"