More descriptive Staking Script Data validation error messages

[gbarkhatov]

Currently, we just have "Invalid script data provided".

[jrwbabylonlab]

This should been resolved now by the #23 PR. The new wrapper class perform a set of validations to check against the inputs before passing to the staking script. The error messages are very detailed in the wrapper class
If no objection, i will close the issue in a few days