AC-1009 Migrate VisitRoomDAO to Kotlin

[wikumChamith]

Description of what I changed

Migrated VisitRoomDAO to kotlin.

Issue I worked on

JIRA Issue: https://issues.openmrs.org/browse/AC-1009

Checklist: I completed these to help reviewers :)

• [x] My pull request only contains ONE single commit (the number above, next to the 'Commits' tab is 1).

• [ ] I have added tests to cover my changes. (If you refactored existing code that was well tested you do not have to add tests)

• [x] All new and existing tests passed.

• [x] My pull request is based on the latest changes of the master branch.