[CP-143] Set 204 code for responses with empty body

Body field was always added to response json, even if
it was containing only null. Now empty body is
not attached to response json, and status code
for such message is set to 204. Additionaly some
minor cleanup in service desktop was done.

[CP-187] Fix stack overflow on passcode decoding

When passcode is passed as json string, each of digits needs to be
parsed as separate character with std::atoi. Replaced the string
with json array of integers to simplify decoding and avoid SO.

[BH-373] Convert utils json into a lib

Moving json to a third-party standalone library.

[BH-370] Convert utils common_data into a libs

Create clipboard and eventsore libs

[BH-369] Turned UTF8 into separate library

Moved utf8 files, formed separate library, fixed include paths,
added utf8 library as dependency to every other target that
uses it, clang-formated utf8 files, cleaned up tests cmake script,
moved utf8 unit test

[CP-140] Deactivate autolock while connected to MC

PurePhone is no longer autolocked, while connected to Mudita Center.

[BH-378] PR changes

PR changes - mainly includes

[BH-378] Style fixed

Fixed style

[BH-378] Utils move log to library

Moved log to separate library

[CP-84] Implement Security API

- Added pass code unlock from MC
- Removed Set USB security status
- Changed isLocked to phoneLocked in request for phone lock status
- Removed remainings of USB security in Settings App
- Reworked USB security model to depend both on
    Phone lock state and Pass code being enabled
- Updated test_security.py

[CP-145] Implement Security Endpoint helper

Added helper and moved out processing code to helper

[CP-148] Fix setting of response in the Parser Context

Incomming ResponseContext was overwritten instead of used.

[BH-353] Add minimal build target for BH

Introducing changes required for adding BellHybird target without
removing PurePhone.
Adden new targets:
* Pure (builds PurePhone and PurePhone.img)
* Bell (builds BellHybird and BellHybird.img)
* [PurePhone|BellHybrid]-[UpdatePackage|StandaloneImage)

[BH-371] Replace gsl with mainline submodule and move to third-party

Replacing loose gsl files with gsl mainline project as submodule
and moving it to third-party

[EGD-6835] Add inotify mechanism in the VFS

Add file monitoring event mechanism to the
VFS subsystem. Now it will be possible to
monitoring file changes in the reistered
path

Signed-off-by: Lucjan Bryndza <lucjan.bryndza@mudita.com>

[CP-77] Replace receivedAt and sentAt fields with createdAt

sentAt json field was never updated and was not used.
Cleaned up DB and DB interface from unused date_send.

[EGD-6701] System time usage fixes

Fixed all calls to stdlib time.
Removed all redundant calls to Timestamp treated as time source.

[CP-120] Fixed USB comm. when Pure reconnected unlocked

USB comm. was secured when Pure was reconnected to PC while unlocked

[EGD-5885] Added SimLockHandler

Refactored LockWindow TitleBar handling. Added Sim pin request
block on lockedPhone. Added Sim info popup added when pin
changed. Updated assets. Removed old PinLock structures.
Cleared LockBox structures. Removed old settings sim setters.
New CellularMessage adaptation. Cleared Lock structure.

[EGD-6736] Add app's state dependent autoLock mechanism

This PR provides the implementation of the auto-locking mechanism that
is dependent on an application's current auto-locking policy. Three
auto-lock policies have been introduced:

* DetermineByWindow
* DetermineByAppState
* PreventPermanently

Also changed the AutoLockWindow set/get auto-lock time value to the
message-based approach.