[BH-1708] Fix buttons behavior

When the button is pressed/released we get an interrupt
which falls or rises edge. We read the gpio state a bit
later so in case of debouncing we can register
the wrong pin state.
After the debounce interval the state is stable.

[BH-1625] The shutdown window doesn't appear while closing the system

Fixed the problem with the not appearing system closing window in some cases

[BH-1532] Changing alarm's trigger time when alarm is snoozed causes several problems

Fixed alarm problems when it was re-set while snooze was still active

[BH-1705] Fixed back button power off timer to 10s

When holding the back button, the device would prompt to
power off after 5s. This was not inline with the manual. Now
the prompt will come up after 10s which is correct by the
manual. In the code, the actual time is set to 9s because
an additional 1s delay is caused by the OS and screen
refresh rate.

[CP-1968] Disconnecting the device during file upload causes problems with the USB

Fixed the problem with an endless loop while sending data
when USB is already disconnected.

[CP-1962] Add Harmony color detection

* Added serial number based Harmony color
detection.
* Unified serial number handling for both
products.

[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

.