Added
* log czmq with logc_czmq
* device token unit tests
* list of times of last received messages for each topic

Removed
* dev folder

Fixed
* device token library - inputs checks
* runnig unit tests in valgrind in no fork mode
* autotools warnings

The folder contained common testing scripts for boxes
connecting to Proxy. The scripts should be packed with each of the
boxes instead to be here.

for each topic.

* update license header
* simplify code
* add tool description
* indent using tabs
* remove useless headers includes
* include missing header

* formating
* indent using tabs
* add license header
* remove useles header includes

* improved description in license header
* indent using tabs
* removed useless header include
* improved doc comments

to handle possible out of range values of input dt_state enum

* check for NULL
* use dedicated macro instead hardcoded length value

proxy_conf struct is designed to be initialized only once.
It has no destructor. So it cannot properly free resources and
be initialized again.

Required to change m4 macro used from the archive to support passing
extra environment to valgrind. We will carry locally forked copy around
for now and will try to upstream it.

Added
* logc - logging support
* connected ZMQ peers monitoring
* check - unit tests
* cppcheck - linting
* lcov - code coverage
* valgrind
* Gitlab CI
* pkg-config and version scripts for device token library
* more fields in configuration file - it can hold the whole config now
* manual overall tests

Changed
* split server CLI option to server and port options
* CLI options - names, arguments and their descriptions updated

config file now can hold the whole configuration

* add disabale server check option
* build server uri from from server and port options

* improve cli options
* add disable server check option
* split server option to server and port
* add more fields to configuration file
* add logging

* improve formating
* variables and macros renamimg
* split server to server and port

* improve build system
* move code to dedicated folders
* add unit tests skeleton