Make yes or no prompts equal

[adpe]

Hi @junpataleta and @FMCorz

Another one. I've noticed that the yes or no command prompts are not throughout case insensitive and there is already an existing nice yesOrNo function in the tools which can be used to solve this issue.

Therefore I've refactored the stuff and provide this patch.

PS: Nice tool! Was working 5 years on daily basis with Moodle but never used it before - just recently discovered the power of this toolkit.

Cheers Adrian