Add the GPS Time field to GPS FIX tab about gpslogger

[GrazianoCapelli]

We'll add the string Time to the strings file, in order to have the translations on Crowdin.

We could check if there is enough space on the screen and, in case, add the Time field (typically in vertical layouts).

[GrazianoCapelli]

During the mock-up phase, I noted that the Time doesn't need a "double-width tile", because the timestamp fits well in a standard one. Thus, when there is space for Time, there is also space for another standard tile. Thus I chosen to show the satellites with the notation USED/TOTAL.

I'm implementing the feature this way:

Since the time is the FIX time, it is expressed in UTC.
I hope that it will be well understandable also without writing "UTC Time" in the description below.

Comments are appreciated.