Add unittest directory, exceptions on offside
remove debug prints
Append solutions with blanks and same letters
add missing files
Merge branch 'testing' into blanks_with_same_letters
update README with the possibility of blanks replacing same letters
update README with command line for unittest
Merge remote-tracking branch 'origin' into blanks_with_same_letters

Conflicts:
	board.py
Merge pull request #5 from flibustenet/blanks_with_same_letters

Blanks with same letters, exceptions with tests