[EGD-6453] Warning when adding incorrect event

When adding to Calendar an event which is incorrect  (e.g. has empty
title or end which is sooner than start) warning window appears.

[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-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-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-5743] Added phone modes popup

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

[EGD-6222] Fix the App Calendar memory leaks

This PR fixes:
 -several explicit uses of `new` that were not matched by `delete`
 -dangling `CalendarTimeItem`s
 -reset of focus on the `allDayEventCheckBox` check/uncheck
 -exiting the app form `allEventsWindow` on `KEY_RF`

[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.

[EGD-5883] Added generic button popups attach to applications

Created structure and implementation for popup windows
attachments on button actions into applications. Moved Volume
window to fit into solution. BarGraph refactored.

[EGD-4157] Actions queue added

All actions shall be queued in order to process them later.

[EGD-5737] Merge master into experimental

Synchronize with master before merging

[EGD-5312] Add Time selection window

- add ChangeDateAndTimeWindow,
- extract EventTimeItem to common widgets folder
  and rename it to TimeWidget,
- extract EventDateItem to common widgets folder
  and rename it to DateWidget,
- replace timeWidget with common TimeWidget
  in NightshiftWindow,
- refactor time setting in
  DesktopMainWindow and TopBar,
- Remove dead code from EventManager
  (GetNextAlarmTimestamp and HandleAlarmTrigger)

[EGD-5737] Merge master into experimental

Keep experimental up to date with changes from master

[EGD-5737] Merge master into experimental

Keep experimental up to date with changes from master

[EGD-5737] Merge master into experimental

Keep experimental up to date with changes from master

[EGD-5737] Merge master into experimental

Keep experimental up to date with changes from master

[EGD-5158] Change access to the bus methods

The bus is now accessible only via Service object.

[EGD-4708] Add backend of multiday events handling

-sql req for multiday events handling
-Add UT
-Add markEventsInDays method
-Add new query for day filter

Merge branch 'master' into stable