minor modifications

README.md

@@ -6,13 +6,13 @@
 
 - [x] Check if we have a file
 - [x] Read file
-- [ ] Check if there are errors in file
+- [x] Check if there are errors in file
   - At least 1 tetrimino or less than 26
-- [ ] Check if every tetrimino is valid
+- [x] Check if every tetrimino is valid
   - 4 char * 4 lines
   - 4 blocks in 1 tetrimino
   - No solo block
-- [ ] Transform file into tetriminos
+- [x] Transform file into tetriminos
 - [ ] Backtracking for smallest square
 - [ ] Transform tetriminos to letters
 - [ ] Print result