Scripts: make confirmations case-insensitive and clarify fails

[jasonklein]

(Temporarily assigned to @rachinkapoor and @kedarchandrayan until re-assignment.)

The scripts executed by run_complete_test_deploy.sh require confirmations, asking: “Do you want to proceed? [Y/N]”.

A Y proceeds; anything else, including y, ends the JS script, but does not end execution of the shell script or otherwise make clear to the user that her negative response will prevent her from successfully completing the next step (i.e., staking and minting).

The following steps should be taken:

• make the JS scripts case-insensitive for confirmations
• exit the shell script upon a negative confirmation
• be more explicit with what is meant in the exit message (I am not certain it is obvious how the user is meant to change the environment variables by, "Exiting deployment scripts. Change the env vars and re-run.")

This relates to #83.