Dates should be localized in english format

Created by: vtexier

The software is in english for now. So dates should be as well.

Created by: vtexier

https://www.englishclub.com/vocabulary/time-date.htm

We are using the "D" format. In that format, british dates can be as French dates. But not american ones. What is our official english language : en_UK or en_US ?

We have no official language, the dates are displayed by Qt depending on OS language.

The bug is more of the other UI not to adapt the system language. It will be fixed later. What do you think ?

Or in the shortterm we can choose a default locale, UK because most of our users are french and this way dates don't change : http://qt-project.org/doc/qt-4.8/qlocale.html#setDefault

https://github.com/ucoin-io/cutecoin/commit/2929944206067c9c2b4a04a3f08abb8b851a4f9a