Restructured project to have logic of each file format in its own file
Use constant for line separator as provided by os module
Minor simplification of string logic
Removed blank line
Fixed loading of .ipuz puzzle to take into account that not all cells may be specified
Use a CrosswordCell by default to store cell data
Allow assignment directly to a cell which will be stored as puzzle key
Make sure we also test it in the reverse order
Renamed attribute to be named 'cell' instead (avoids confusion with puzzle object as whole)
Added instructions to README on how to get the cell's content
Always call parent init method whenever we have defined our own
flake8 line length cleanup
Removed cleverness and simply use attributes to store cell content and properties
Let CrosswordCell take care of string representation
Updated exception message with a helpful hint
Added ability to set a dictionary directly to a cell location
Automatically convert assignment of a string to the cell's 'cell' attribute