From investigation in SERVER-115408, we determined that one of the key interactions between the checkpoint manager and the log server manager is that the 
LogServerManager provides getCheckpointManager() and a couple bare delegate functions to provide access to CheckpointManager to other classes (state machine and repl coord). 

To address this, we will remove the delegation and have other classes keep a pointer to checkpointManager. This will be done by first separating the build targets (then in a separate ticket, removing the delegates)

Acceptance criteria:

Pull checkpoint manager to its own build target with an abstract header. Use dependency injection to provide the CheckpointManager to the LogServerManager.