Log user session command
For sessions, prefer .desktop files if they exist

When using sessions, prefer .desktop files, if they exist.

This also allows for example to configure Session=plasma
in the autologin section, instead of having to add the
.desktop extension.

[ChangeLog][Daemon][Display] Automatically append .desktop extension
to sessions if the corresponding file exists.
Log desktop file
Fix session index check
Estonian translation

Add Estonian translation from Jüri Ivask <Jyri.Ivask@mail.ee>

[ChangeLog][Translations] Added Estonian translation.