Encounter.getConditions and Encounter.removeCondition to handle voided conditions

1. Description

Encounter.getConditions() being the only such "get all" getter should filter out voided conditions by default. A boolean parameter should be introduced on a new getter to allow including voided conditions if desired.

Encounter.removeCondition(Condition) should not remove the condition but instead leave it in and void it appropriately. Very much like things are done for the encounter's providers.

2. References

• 'REST Web Services API Including Retired metadata and Voided/Deleted data'

3. Dev Notes

• See Encounter.getConditions()
• See Encounter.removeCondition(Condition)
• As an example, how providers are removed: https://github.com/openmrs/openmrs-core/blob/2f3e2928f84498c431a775a86930956a87a15377/api/src/main/java/org/openmrs/Encounter.java#L783-L793

4. Acceptance Criteria

We need to expand the test code base to properly reflect that those methods behave as expected.