GSoC Journey: Week 10

As the patient search criteria module is working perfectly, it is time to move the functionality of the module to the openmrs core, as this is the main goal of the project. This was the task of this week.

To add the functionality of the module into the core, I added the class and related functions in the core. Also, I tried to reduce the size of code by using the Java stream API.

My PR: https://github.com/openmrs/openmrs-core/pull/2980

To actually use the patient search criteria, I also need to create REST resources, for that, I need to perform the changes in patient search handler in webservices.rest module. This is my goal of the next week.😃