[EGD-6641] Added Notifications to LockedPhone popup

Added NotificationsModel to LockedPhone popup window.

[EGD-5884] Added Lock Screen popup handling

Moved lock screen window to popup. Split DesktopMainWindow into
two parts (popup and regular). Added LockPhoneHandler into
ApplicationManager.

[EGD-3119] Hide InputEvent's member fields

Use the InputEvent's convenience methods to express intent.

[EGD-6637] Cleanup locks structure

Renaming existing locks namespace and created proper directory
structure.

[EGD-5703] Fix SimCard topBar icon on Desktop

In initial design a `TobBar`'s SimCard icon with number is supposed
to display on the home screen only if there are two cards inserted.
Because of the hardware limitations (there is no way of telling if
there is a single or two cards inserted) the established consensus is
that home screen should not display SimCard widget unless it's
indication error state.

Although in the task description there is only home screen mentioned,
the behaviour was established for all `ApplicationDesktop`'s windows.

[EGD-6456] ListView based desktop notification

This PR provides following changes in notifications:
- notifications were extracted as widget for pop-up-based
locked-screen implementation
- notifications are ListView based implemented
- the most recent notification is displayed on the top of the list

[EGD-6513] Volume control feedback

Added volume control feedback during music playback over Bluetooth.
Changed volume buttons handler logic in service audio to use actions
instead of messages.

[EGD-6301] Add Connecting to the network in intervals

It implements mode Offline Messages only - connecting to
the GSM network in defined by user intervals and rejecting
incomig calls during connected phase. It also implements
handling of connetion interval setiing and small fix in modes
popup.

[EGD-6485] Remove Cellular message types from global

Domain-specific message types should not pollute global space.

[EGD-6093] Audio settings API

Refactored Audio settings API.
Moved phone modes logic from serivce audio to service clients level.
Removed redundant API.
Seprated API for vibration and sound enable/disable.
Fixed issues with vibrations logic.

[EGD-6505] Implement “On when active” Keypad light functionality

Implement “On when active” Keypad light functionality

[EGD-6486] Fix for settings not avaialble at phone startup

Fixed the comparison function of EntryPath objects.

[EGD-6494] Application Manager on action switch fix

Application Manager switch on Action no longer causes to
newly opened application main window switch but it
calls declared action handler.

[EGD-6347] Refactored phone modes handling in applications

PhoneModeObserver doesn't work properly in applications.
Applications have to handle the phone mode changes via AppMgr.
Phone mode and tethering handlers separated.

[EGD-6208] Add blocking phone mode changes during tethering

When the tethering is enabled, the phone mode shouldn't change,
now, any attempt ends with a notification

[EGD-6209] Tethering confirmation popup added

Provided a tethering confirmation popup.
The popup shows up once a USB cable is connected to a PC.

[EGD-6304] Popup overall fixes

Removed duplicated mode observer from application
that was introduced during the rebase in this commit
1860bf210f5f128ee8cf780c0cb332abc918dbd1.
Fixed mute logic according to the design.
Fixed switching back to the meditation window.

[EGD-5744] Phone mode status bar widget

Added phone mode widget to top bar. The widget is mutually exclusive
with NAT widget. Phone mode is determined using phone mode observer.

[EGD-5743] Added phone modes popup

Implementation of phone modes window.
Minor fixes of previous approach.

[EGD-5712] Volume popup added

There is need of popup window on volume key
pressed event. This PR handles:
Creating base popup window attached to
application desktop.
Creating volume window.
Audio key events logic implementation.