Implemented regex and validation helper functions and fixed some bugs

Added regex helper function which turns a comma separated numerical range (i.e. 1,2,5-10) into a regular expression for matching.

Also added a some validation helper functions which can test to see if specific arguments are provided etc.

Lastly fixed an issue where bashr.sh Setup function fails exit on a non zero code when it fails. This is an issue when determining the success/failure of a script based on exit codes.