[EGD-6583] Add send text

Adds missing send text during
incoming call.

[EGD-6600] Add rejected call message

Adds rejected call message
instead of ended call.

[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-6506] Turn on function keys backlight during call

Backlight of function keys are on when call is active.
When call ends, previous backlight mode is restored.

[EGD-6527] Internationalization API unification

Single api to rule i18n
all calls to localistaion in cpp files unified
cut off ass many dependencies in i18n header as possible

[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-6515] Answer/reject calls using headset

Clean up propagation of headset keys events
Clean up volume control with headset keys
Update key mappings for simulator
Use headset OK key to answer/reject calls

[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-6324] Update audio assets

Upload latest audio assets. Original file names preserved.

Signed-off-by: Marcin Smoczyński <smoczynski.marcin@gmail.com>

[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-6121] Add offline mode in service cellular

Adds entering and leaving ito offline mode in sevice
cellular. Outgoin SMS and calls are blocked Proper popups
are shown in applications Call and Messages.

[EGD-6314] Phone mode widget visibility

Phone mode widget will be visible only on main screen, while entering
numbers or in emergency call mode. Also it will be disabled whenever NAT
widget is enabled.

[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.

[EGD-6111] Timers refactored

Deep refactor of system timers.

[EGD-5449] Add final prompts windows

Added Dialog windows for "configuration successful"
"no configuration" and "update OS" for Onboarding.
Refactor Dialog window implementation and usage of
DialogMetadata in other applications.