[Spring] Create an endpoint to get alerts with pagination

[suksw]

Following is only a suggestion. Please make any necessary changes.

Endpoint: GET http://localhost:8000/application/alert

Requirements for the API request:

1. specify "last updated date" (optional) : so that all records added/updated after that can be included in the response
2. specify "page" (optional) : index of the chuck
3. specify "page size" (optional): the number of alerts to be returned

If none of the above are given we could return the a "max_page_size" response where the "page" is 1.

Requirements for the API response:

1. All three above
2. Boolean value to indicated whether there are more left
3. of course the alerts list