httpendpoint: Reduce critical region using atomic variables

This way problems related to object destruction are solved

Change-Id: Ib80c30d178b3c03b4f7df6b05d447472d0a58615
Set internal pipelines "async-handling" property to true

This way we avoid deadlocks while changing its state.

Change-Id: I45832b723169aad626ff68f47ef3b253b4205628