Fixed warning about ssize_t to int conversion

Signed-off-by: Ilya Mikhaltsou <morpheby@gmail.com>
Incapsulated exit flag in SerialComm, with integrated mutex lock

Signed-off-by: Ilya Mikhaltsou <morpheby@gmail.com>
Started util::Atom implementation

Signed-off-by: Ilya Mikhaltsou <morpheby@gmail.com>
Fixed const marker -- mutex operations not valid on const mutexes, obviously

Signed-off-by: Ilya Mikhaltsou <morpheby@gmail.com>
Test implementation of Atom

Signed-off-by: Ilya Mikhaltsou <morpheby@gmail.com>
Finalized atom implementation

Signed-off-by: Ilya Mikhaltsou <morpheby@gmail.com>
Integrated util::Atom to SerialComm where possible

Signed-off-by: Ilya Mikhaltsou <morpheby@gmail.com>