Created new statuses for the fixture removal workflow.

AFDP-105
Created new command to initialize the remove fixture workflow.

Updates the fixture status appropriately, but doesn't delete it.

AFDP-105
Created unit test for new command.

AFDP-105
Created new notification for reporting the fixture was removed.

AFDP-105
Added new task/result to support the remove fixture workflow.

AFDP-105
Added remove fixture task result handler and unit tests.

AFDP-105
Added remove fixture functionality to the task enroller.

AFDP-105