N-Queens-Puzzle solver

The definition for problem - https://en.wikipedia.org/wiki/Eight_queens_puzzle.
Kotlin's implementation using backtracking and branching reduction. Uses BooleanArrays to keep track of occupied diagonals. Which appears, according to profiler, to be more effective than Sets.

Implementation is looking for all possible solutions, not only for fundamental ones. Probably I missed the important requirement here, but reference implementation is also provided all solutions.
No multithreading - just single threaded implementation.
On my machine 15x15 solution runs about 15 sec (without printing out found solutions) and 16x16 solution runs about 90 sec.

to build

./gradlew clean build

to run

• unpack distribution
  cd build/distribution
tar xvf n-queens-puzzle-0.0.x.tar or unzip n-queens-puzzle-0.0.x.zip
cd n-queens-puzzle-0.0.x/bin
• use -h or --help for command line parameters, e.g. -v or --verbose to print out found solutions, -n N to set the board size
  ./n-queens-puzzle -v -n 4 or n-queens-puzzle.bat -n 8