Clarify Rails Generator User Prompts

[nomadicoder]

Cross Reference: #345

Follow installation guideline in https://github.com/projecthydra/curate/blob/master/README.md

With regards to the prompt, "Type y(es) to confirm:". Users may think that hitting 'return' is equivalent to hitting 'yes', but the user must type 'y' or 'yes' to confirm. Make it clear that typing 'y' is the answer to confirm, such as "Type 'y' to confirm:".