ADD: Non-blocking input stream.

Because of the chat window constant re-drawing, the echo of the input stream will disappear.

The INonBlockingInputStream enables the reading of each separate
characted from the stream, at the moment of the pressing of the key, so
whatever is typed is saved in the memory and displayed when the console
is re-drawn.
Even more, the INonBlockingInputStream turns of the echoing, so the
input is only displayed when the console is re-drawn.

The logic of the class is written in C (so it's OS
specific) and it's executed through the JNA API.

For the moment, only Linux is supported.
ADD: IChatClient interface.

The intefraces describes the chat clients - the objects that represent
the participants of the chat.
ADD: InputReader class.

The class is specially designed to read from an
INonBlockingInputStream instance. It blocks while reading a whole line,
while giving beeing able to return a String of what is read so far (but
only if invoked by another Thread).
FIX: VerticalFramesStack bug fixed.

While getting a given line, the first line of each subframe was skipped.
EDIT: Frame rate control added to console.

The LinuxConsoleWindow uses the new FrameRateController abstract class
to controll the number of redraws of the console per second.

The controller sets a limit of ~30fps, but the console is redrawn only if
some class calls the scheduleRender() method. The idea is, that if
multiple renders are scheduled, they all will be rendered together and
the user will not even notice a delay.
ADD: A ConsoleFactory class.

The factory instantiates a different console, depending on the OS. Each
console uses a different INonBlockingInputStream implementation, which
is OS dependant.

Only Linux is supported for now.
EDIT: IChatWindow interface changed.
EDIT: ChatStreams refactored.
EDIT: All console implementations moved together.
EDIT: POM and Main class.