Starting from zero
Creating method to validate if the character is a valid roman letter
Asserting true and false cases for method isValidLetter
Adding method to test if the letter is repeatable
Changing method isRepeatableLetter to verify if the letter is repeatable or not
Added a new method to converto roman to integer
Added a new test case for method toInteger. Verify if V is 5
Created a test that assert if II is 2
Asserting if the result of converting VI to integer is 6
If current letter is has a greater value than previous letter, substract the previous letter from current one.
Improving the rule that verify if the previous number is lower or greater than the current number of the iterated sequence for method toInteger. (Asserting if XIX produces 19)