Changed anonymous enum to #defines.  Replaced const bool & and const int & with bool and int, respectively.
Renamed flag override to force_insert.
Added newline as per clang warning -Wc++98-compat-pedantic
Pulled some std::pair access out to the top of set_piece
Bool win was comparing to an int.  Fixed that.
Altered board printer to place (0, 0) at the upper-left corner.  Altered water-fill code in board's no-param constructor to directly assign rather than try to give Water a direction.
Pulled bounds checking out into a private member
Pulled out random number generation into function.
Fixed tester.  The tester was broken by the commit that filled the board with Water.
Rolled up set_their_board with a helper function.
Rolled up set_your_board with a helper function.
Added a function to solicit a coordinate pair from cin.
Defined operator<< for Coordinates.
Changed fire counter implementation from doubly-nested vectors to vectors of Coordinates.
Changed names of fire counters for both players.
Wrote coordinate_is_not_water helper
Fixed our hit check.
Wrote a GuessBoard, which obscures the types of ships when printed.
Switched the printed board over to a GuessBoard populated by the user's guesses.
Fixed the computer's hit check.