Radius (#7)

* Radius. Header file <mutex>, <jthread.hpp> added. Functions start, stop
declaration changed. Class members m_thread, m_mutex added. Function Run
declaration added.

* Radius. Header files added. Functions Start, Stop, Run definition added.

* Radius. New files server.h, server.cpp added.

* Radius. Definition of functions startReceive, makeResponse, handleSend,
handleReceive added.

* The Run function name fixed. Definition of secret variable sdded.

* The file server.cpp added to add_library command, command
find_package(OpenSSL 1.0.0 Required) added, OpenSSL::Crypto added to
target_link_libraries command in the block if(BUILD_MOD_RADIUS).

* Parameter token added to function Run() declaration.

* Radius. Method Start: variable isRunning=true removed, m_thread
definition changed. Method Stop: variable isRunning=false removed,
m_thread.joinable check added, isRunning check added, request_stop call added.
Method Run: parameter token added, variables secret, port removed,
object lock and isRunning=true added before cycle while,
cycle while added, isRunning=false added after cycle while.

* Radius. Hold the mutex removed,extra conditions
for m_thread.join() removed in the Stop function.

* Radius. Cycle while removed in function Run.

* Radius. The variables isRunning, errorStr replaced by m_running,
m_errorStr in class Radius.

* Radius. The variable isRunning replaced by m_running in function Run.

* Radius. Object name io_service changed to ioService in the function Run.

* Method SetRunning declaration added to the class RADIUS.

* Method SetRunning definition added. Method SetRunning call added to
function Run.

* Radius. Namespace STG added.

* Radius. Declaration using STG::Server added.

* Radius. Header file "stg/logger.h" added. RADIUS class member m_loger added.

* Radius. Header file "stg/common.h" added. Initialization of m_logger
added to constructor RADIUS. Output cerr replaced by logger and
printfd().

* Radius. Variable except added, messages fixed in the function Run.

* Radius. Thread join logic fixed in the function Stop.

* Keyword const added to std::lock_guard in the function SetRunning.

* Radius. Class member m_mutex moved to the top of list.

* Radius. Class member m_logger put after the m_running.

* Radius. Unnecessary variable except removed in the function Run.

* Radius. Extra whitespace removed in the function Stop. Function
IsRunning definition added.

* Radius. Function IsRunning declaration changed.

* Radius. Formatting fixed.

* Radius. Extra symbols '//' removed.

* Radius. Class member m_running initialization added to constructor
RADIUS.