[BH-2019] Fix crash after deleting WAV alarm sound

Fix of the issue that the device would crash
when entering alarm sound selection list
after deleting selected file during alarm
ringing, but only when file's format was
WAV.

[BH-2020] Fix double-free in DecoderMP3

Fix of the issue that improper check
of dr_mp3 library initialization
success could result in double-free
of library internals in case
initialization was unsuccessful.

[BH-2005] Add volume setting for focus timer

The user will be able to control the volume of notifications in the
Focus Timer application

[MOS-1068] Fix A2DP stream not restarting after song changes

Workaround for the issue that A2DP stream
would sometimes not restart when music
player changes song to the next one.

[BH-1898] Fix of GUI freeze after intensive volume change

Fix of the issue that GUI would freeze for
several seconds if volume level was being
changed intensively for a while.

[BH-1888] Fix device freezing when changing volume intensively

Fix of the issue that intensive changing
volume in Relaxation app would result in
device freezing after some time of such
activity.

[BH-1863] Fix deleted file popup showing in Relaxation

* Fix of the issue that 'File has been
deleted' popup would show in Relaxation
app at the end of playback if the
playback was paused at least once,
even though the file wasn't actually
deleted.
* Added very basic audio decoder error
handling and propagation mechanism.
* Minor refactor around several
audio-related parts.

[BH-1836] Increase range of volume adjustment

Extended volume scale from 10 to 15 point scale
Modified volume approximation function for better user experience

[BH-1264] Add alarm sound fade in

Adding a fade in for the alarm sound (main and power nap) according to
the pattern (V): dt = 30[s] * V/10.

[BH-1823] Fix relaxation start delay for specific MP3 files

Fix of the issue that when trying to play
files with large ID3V2 metadata the
playback would start with significant
delay of several seconds. It was also
possible to leave relaxation progress
window without stopping the playback.

[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-30] Fix for Alarm not being handled properly during a phone call

During the phone call, the alarm was not displayed and subsequent alarms
after this scenario did not work. This has now been fixed and the alarm
during a phone call will be automatically snooze.

[MOS-878] Don't break audio playback on file deletion

Since a currently played file is deleted, the player
goes to the next file from the list. A special case:
if the deleted file is the last one, the playback
stops (and can be resumed by the user).

[MOS-871] Loudspeaker icon is not updated when audio routing has changed

Fix for the loudspeaker becomes active again when a headset is unplugged
if it was on while the headset was connected to the phone.
Fix typo in Bluetooth in EventType enum.

[MOS-882] Fix heap fragmentation issue during playback

Fix of the heap fragmentation issue that caused
phone crash when trying to play music files
while connecting USB cable in a certain order.
Audio stream buffering length was slightly
reduced, so that smaller contiguous block of
heap is required to store audio buffer.

[MOS-882] Fix FLAC file playback with USB cable connected

Fix of the issue that caused system crash when
trying to play 96kHz FLAC file with USB cable
connected. The reason of the issue was the lack
of FreeRTOS heap space left, what caused
pvPortMalloc() to fail when allocating
memory for stream buffer.

Additionally minor code cleanup.

[MOS-783] Moved battery config file to '/user/data'

Moved battery config file from root
directory of user partition to
'data' directory to comply with
new directory layout design.

[MOS-783] Working Pure simulator after partition changes

Fixed iosyscalls so that Pure simulator
works after directory structure changes.

[MOS-783] First part of new dir structure implementation

    Works:
    - generating .img for Pure;
    - Pure boots after flashing new image and
    seems to be working fine;

    Not yet:
    - generating update package;
    - generating image for Harmony;
    - simulator;
    - path-related unit tests fail
    due to paths being hardcoded
    in test scenarios.

[MOS-814] Fix no sound after BT device connection during call

Fix of the issue that connecting or
disconnecting BT device while call
was in progress resulted in no sound
being heard anywhere due to audio
routing being stopped when HFP device
disconnected.

Additionally minor code cleanup.