Add option to disable --no-mtime flag

[Maxstupo]

For the time being I will have to use version 2.7.0 since version 2.8.0 does not keep the original date and time set by the server. Is there an option to revert this behaviour? If there is no such option I would like to suggest that you add a new check box, perhaps in Download tab in Settings:

• Keep the file date and time as set by the server

Or something like that. For me keeping the original date and time of a file is essential and important. Please consider adding such an option as a new check-box (it may be disabled by default).

Originally posted by @smaragdus in https://github.com/Maxstupo/ydl-ui/issues/83#issuecomment-856376797

[smaragdus]

@Maxstupo

Thank you very much for accepting my request! I didn't open a new issue myself because I thought that my suggestion was closely related to issue #83.

[smaragdus]

@Maxstupo

Many thanks for adding this new check-box:

• Keep original date and time

I have just downloaded and tested version 2.8.1 and the new option works as expected preserving the original date and time of the videos.

This option is very useful for me.

When I discovered your program in the autumn of 2018 (the first version I used I believe was 1.4.5) I didn't expect the development and maintenance to be so persistent. Thank you very much for all your work on this project!

Best regards