API update

	* Property indicates whether the unit is encircled

Signed-off-by: Ladislav Klenovic <klenovic@nerdrobot.net>
New game board state helper method

Signed-off-by: Ladislav Klenovic <klenovic@nerdrobot.net>
Minor refactor

Signed-off-by: Ladislav Klenovic <klenovic@nerdrobot.net>
API update

Signed-off-by: Ladislav Klenovic <klenovic@nerdrobot.net>