[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.

[BH-1787][BH-1802] Bump Harmony Ecoboot version

Ecoboot version changed from 2.0.5 to 2.0.6.

[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.

[BH-1696] Charging notifications improvements

Fixes and improvements for charging notifications

[MOS-1051] Updated HNI codes for VoLTE support

Reviewed and updated HNI codes lists
for all countries with VoLTE support.

[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

[BH-000] Update changelog for 2.2.1

Update Harmony's changelog after releasing MuditaOS 2.2.1.

[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.

[BH-1791] Add CPU frequency lock during log dump

This will improve security and peripheral stabilization when downloading
logs to a file.

[BH-1801] Fix incorrect calculation of requested CPU frequency

Sometimes when the frequency is locked, e.g. at 132 MHz, the algorithm
still calculated a lower frequency, e.g. 66 MHz.

[MOS-996] Disable MTP protocol

Disable MTP file transfer protocol.

[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

[MOS-1050] Add missing Germany HNI codes

Updated list of operators' HNI codes
in Germany, added missing ones.

[MOS-000] Update Pure 1.9.0 changelog

Update Pure's changelog after releasing
MuditaOS 1.9.0.

[BH-1784] Replace discharged device screen

Add more information to discharged screen

[MOS-1048] Fix not fitting VoLTE button label

Fix of the issue that VoLTE checking
state label was cut off due to
improper setMinimumWidthToFitText()
method behavior when text is placed
in box with rounded corners.

[MOS-1046] Update module-services/service-cellular/call/doc/README.md

Typo in documentation module-services/service-cellular/call/doc/README.md
The state machine library is called `sml`, not `stm`.