Merge pull request #4 from EliasEriksson/dev

changed from if check to atempt to parse integer from tesseract scanned string. got some wierd characters out from empty fields ocationally. this should make sure only numbers go through.

Update README.md

added license

Merge pull request #3 from EliasEriksson/dev

Ready fo merge with master.

Moved the last methods referring to Field.board_coordinate to the Field class.

Refactored many methods outside of the Field class to not use Field.board_coordinate. Instances of the class is now directly passed or used directly instead.

no longer loops over "uninteresting" numbers.

combined the advanced algorithms under one function and let both exhause the entire field before returning.

The more advanced algorithm now works (at least so far).

the advanced algorithm should work now.

the advanced algorithm should work now.

good progress on more advanced algorithm.

partial progress on extending the algorithm.