Feat change path error checking colored errors

[samej71]

This adds

• The ability to change the path from /opt/tmp within the script
• Will display message and prevent some commands from executing if the path doesn't exist or is not writable
• Added some error checking so destructive commands do not execute if the save/backup command(s) fail

Quickly written and not yet thoroughly tested after installing and running this program for the first time and selecting option 7 because my NVRAM is almost full and I need to recover the space, only to have the backup fail and the things I wanted to keep erased without a backup.

My first PR, and I'm sure I did not follow protocol :) I tried to follow the coding style already in the script.