[BH-1647] Add serial number to about section

Added serial number entry to about window

[BH-1690] Add information about the connection to the PC

Added text with information about the connection to the main window
when the USB cable is connected to the PC

[BH-1695] Fix Harmony crash on startup

Fix of the bug in PWM driver that
resulted in accessing array out of
bounds, what caused occasional
system crash on startup.

[CP-1966] Deleted file which is played does not stop the playback timer

Fixed the timer issue when file was deleted during playback.

[BH-1691] Change the layout of the battery status

The new layout of battery status has the battery
SOC on the left side and battery image on the right.

[CP-1937] Amount of space assigned to "Other" changes after uploading audio file

Fixed by sending information about device memory in floats instead of
uints

[BH-1595] USB charger detection issues

* Fixed issues with USB charging port detection
* Fixed memory leak in usb_stack/OS integration layer
* Fixed incorrect handling of software timer
* Minor cleaning/refactor.

[BH-1595] Turned off USB/PC charging

Charging enabled only for a dedicated charger. Users won't be able
to charger while connected to the PC.

[CP-1841] Distorted playback and poor device control responsiveness

Fixed problem with an unresponding device after playing specific WAV files.
WAV files encoded with ADPCM are not supported now by the devices.

[BH-1671] Reinit eMMC driver

Reinit eMMC driver if write/read transmission
failed.

[BH-1661] E-ink display power management tweaks

Tweaks and changes required to optimize
power consumption for Harmony.

[CP-1939] Difference in displaying file name for list and for loop play function

Fixed problem with displaying end of title when playing song in loop was
selected.

[CP-1938] UI issues when uploading multiple copies of a specific file

Fixed problem with badly calculating characters to show which cause a
problem with displaying text on UI.

[CP-1852] Too many user files removes default relaxation audio from the list

Changed order in which files in Relaxation are displayed
Added error message when files limit is exceeded

[BH-000] Update changelog for 1.8.2 and 1.9.0

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[BH-1650][BH-1651] Fix the frontlight settings

Run the frontlight settings in "on demand" mode now
turn on the backlight with the proper intensity.
If the device is idle in the frontlight settings the backlight
isn't turn on after backing to the main window.

[CP-1842] Extremely long title tag causes delay when loading Relaxation songs list

Fixed by limiting the maximum text length in relaxation main window

[CP-1837] Random crashes while copying files

General improvements to prevent running out of memory while copying
files via Mudita Center

[BH-1654] Change polish meditation summary text

Use gender-neutral version

[CP-1848] Problems with displaying file names

Added missing characters to font 'gt_pressura_light_46' used in Relaxation

[BH-000] Update changelog for 1.8.1

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