[BH-1809][BH-1835] Add date format setting

Added date format selection between DD/MM and MM/DD.
The time setting has been updated.

[BH-1828] Add labels to relaxation sound list

Added labels to relaxation

[BH-1648] Add shortcuts instruction to settings

The user should be able to return to the shortcuts instruction at any
time. The instructions are available in the settings.

[MOS-1052] Change VoLTE label from 'beta' to 'experimental'

Changed VoLTE label from 'beta' to
'experimental'.
Fixed transition state label font
size to match the design.

[MOS-896] Update low battery screen view

Updated low battery screen view by adding
info windows appearing when trying to
interact with phone having critical
charge level.

[BH-1696] Notification when connect the device to the charger

Adding notifications when charger is connected

[MOS-669] Add too hot battery notification when charging

* Added notification showing on the main
screen if the battery has reached too
high temperature to continue charging.
* Code cleanups.

[MOS-1033] Add 'beta' label to VoLTE switch for selected countries

Added mechanism enabling to individually show
or hide "beta" label on VoLTE switch for each
country.

[MOS-1007] Fix for no popup when contact cannot be saved because of same nubers

Fix for fix. It add popup when user try to save contact witch practically
the same numners  (even if having a country code is only difference)

[MOS-1020] Fix for losing unsaved data

Fix for losing unsaved data when the user click the BACK button while
creating or editing note/contact.

[MOS-930] Change translations for Old Messages text

Change translations for Old Messages text to Previous Messages text.

[BH-1749] Fix diacritics in translations

Some texts did not have diacritics in the translations

[MOS-930] Fix for for misunderstanding holes in sms conversations

Not all messages can fit on the current screen in sms conversation windows,
so there may be some holes that might suggest that  there are no more messages
to display. Now, when therea are more SMS to see by scrolling up,
the Old Messages label will indicate this fact.

[MOS-1002] Change USSD code handling to match design

Fixed issues with GUI behaviour on failed
USSD code handling.
Minor code cleanup in several parts of system.

[BH-1733] Add Harmony version information

In the Settings->About section, we will have information
about which version of Harmony the user has.

co-author @Lefucjusz

[CP-1962] Add Harmony color detection

* Added serial number based Harmony color
detection.
* Unified serial number handling for both
products.

[BH-1690] Add information about the connection to the PC

Added text with information about the connection to the main window
when the USB cable is connected to the PC

[CP-1966] Deleted file which is played does not stop the playback timer

Fixed the timer issue when file was deleted during playback.

[MOS-578] Fix misleading SMS notification text

Display "New message", translated accordingly - in
singular - in case there had been multiple unread
SMS messages and now only one remains unread.

[MOS-933] Added translations for Bluetooth connection status

Ditto