[BH-1657][BH-1833][BH-1854] Add WFI and SDRAM self-refresh mode

* Added mechanism enabling CPU to
enter WFI mode when the OS is
in idle, what results in large
power consumption reduction.
* Added mechanism to switch SDRAM to
self-refresh mode before entering
WFI, what resulted in further power
consumption reduction.

[BH-1807] Fix missing AM/PM label in apps clock

* Fix of the issue that after changing font size
of the clock presented in Relaxation, Meditation
and Power Nap apps, AM/PM label was not shown
in 12h mode.
* Added logs informing about missing margins
map entry so that such issue is easier to debug
if it should happen in the future.

[BH-1731] Fix factory reset confirmation window layout

* Fixed factory reset confirmation window
layout to match the corresponding design.
* Added missing translations.

[BH-1845] Fixed time format in Settings and Onboarding (2)

This is the second fix. Now the time format in Settings and Onboarding is currently set
and changes dynamically during the user changing the time parameters.

[BH-1807] Increase clock font

Increase clock font in Relaxation, Meditation, Power nap mode

[BH-1825] Remove minus sign in countdown timers of progress

Removed minus sign shown next to the remaining
time value for timers showing progress in
Meditation, Relaxation and Power Nap apps.
Style constants cleanup.

[BH-1826] Implement new countdown progress bar design

Implemented new countdown progress bar design,
used in Relaxation, Meditation and Power Nap
apps. New implementation shows progress
bar as decrementing as the time passes instead
of incrementing.
Cleanups.

[BH-1731] Factory reset removes user files

Performing the factory reset removes user files
and settings. After powering on the device
will run the onboarding.

[MOS-1060] Fix memory leak in contacts list view

Fix of the memory leak that happened in
contacts list view due to not deleting
unused heap-allocated object.

[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-1782] Add brightness fade in

* Added brightness fade in - feature
which allows for gradual frontlight
brightness rise during alarm and
power nap ringing instead of turning
on with full brightness immediately.
* Fixed possibility to close
ringing power nap by long press
of back button.

[MOS-1056] Hide the SOS label when the modem is not ready during onboarding

Hide the SOS label during onboarding when the modem is not ready for an emergency call.

[MOS-220] Changed signal strength refresh mechanism

Modified signal strength update mechanism
to avoid unnecessary screen refreshes in
case new signal strength value is equal
to the previous one.
Minor cleanups.

[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-498] Change input language with the change of the system language

Now when the user changes the system language, the input/keyboard language
will change automatically (in the background).
If the user changes the input/keyboard language, this will not change
the system language.

[MOS-644] Displaying number entered on the keypad during a call

Now, on the active call screen, the user can see the numbers provided during the call,
which is useful when, for example, the user calls a call center.

[MOS-1042] Fixed inability to save a contact that did not previously have a phone number

Fixed inability to save a contact without a phone number
when contact lose the number after replace similar number and
visibility of the SAVE button when editing/creating a contact.

[BH-1688] Create a standard for logs

* Adding document describing how to use logger
* Adjusting logs to follow a new guide
* Change order in log header:
  line number is now before function name