Modified is_power_of_two to include contracts. Also modified affected tests
Merge branch 'client_server' of https://github.com/nmaguirre/eiffel-2048 into client_server
Merge branch 'client_server' of https://github.com/nmaguirre/eiffel-2048 into client_server
Merge branch 'client_server' of https://github.com/nmaguirre/eiffel-2048 into client_server
Merge branch 'client_server' of https://github.com/nmaguirre/eiffel-2048 into client_server
Merge branch 'client_server' of https://github.com/nmaguirre/eiffel-2048 into client_server
Minor change in is_power_of_two_at_cell_2048 tests
Merge branch 'client_server' of https://github.com/nmaguirre/eiffel-2048 into client_server
Merge branch 'client_server' of https://github.com/nmaguirre/eiffel-2048 into client_server