Bug in setting the 'lexorank'

[colideum]

Hi, Maybe it's a functionality, but anyways. Steps to reproduce:

• try to add 6 goals or activities or features or mvps one after each other
• 6th item will not be added because of database constraint, which is related to the rank

When i reviewed the code i've noticed that lexorank is adding ranks interestingly, it always sets mid item between minChar and maxChar, so the first rank in the branch will always be 'm', then it will follow 's', 'v', 'x' and 'y'. After that mid character will still be 'y' as it check with the highest item and then decreases one byte down.

I didn't dig deep into the whole logic, but i think it should be reconsidered or fixed. But there is still a possibility to avoid the problem by moving 5th item before 4th item. Then 5th will become 'w' and for 6th it still will be possible to add 'y'.