added methods that implement the RSA algorithm for ecoding and decoding person_id
this is a template configuration file that stores the keys for ecoding and decoding. To use this file, rename it from 'kubisa.yml.example' to 'kubisa.yml'. Kubisa.yml should always be kept locally just like 'database.yml' since it contains key for encryption
a sample list of prime numbers that can be used by kubisa for generating data ecryption keys. By running the method 'Openmrs.generate_keys(prime_a, prime_b)': this method will return keys that can then be kept in the file 'config/kubisa.yml'