Display time zone in metadata panel XMP date/time fields

[jch2103]

Based on the recent discussions about time zones, it would be useful if metadata panels could display any applicable time zone information, if present. This would only apply to XMP metadata fields, because EXIF fields can't contain time zones.

I don't know how easy this would be to implement, given that Windows locale settings affect date/time displays. But it might avoid some of the issues of showing times for photos taken away from the computer's local time zone.

For example (assuming time zone information is present in the XMP metadata field):

A photo taken at 10 in the morning on New Year's Day in London would display for Original Date and Digitized Date (in US settings) as
1/1/2014 10:00:00 AM UTC+00:00

A photo taken at 10 in the morning on New Year's Day in New York City would display for Original Date and Digitized Date (in US settings) as
1/1/2014 10:00:00 AM UTC-05:00

A photo taken at 10 in the morning on New Year's Day in Brisbane would display (in US settings) as
1/1/2014 10:00:00 AM UTC+10:00 (no daylight savings time in Brisbane!)

A photo taken at 10 in the morning on New Year's Day in Sidney would display (in US settings) as
1/1/2014 10:00:00 AM UTC+11:00 (DST in effect in Sidney)

A photo taken at 10 in the morning on New Year's Day in Berlin would display (in US settings) as
1/1/2014 10:00:00 AM UTC+02:00

If there's no time zone set for the image, the time zone ideally would be suppressed in the display, e.g.:
1/1/2014 10:00:00 AM

[Mario]

This has already been changed for the upcoming 5.0.158 build.
Also variables now display the time zone if a value:formatted or value:raw is used.