Refactor and format code, clarified some comments
Refactored word search generator fixed bug that in arePossibleInstancesSatisfied wasn't extending possible instances when next character is empty and isn't end of word
Refactored areAllOrientationsValid to be more readable and effective in detecting both reversed and not reversed possible instances. Handled edge cases better, when detecting if possible instances exist
Added parameter in constructor that allows you to choose whether to fill the word search with alphabet characters or characters from the word