Module Timing

[nsoblath]

Each module of Hornet should time how long it takes to process each file.

The original motivation for this is to measure data transfer rates in the Shipper, but it could be applied to all modules.

[nsoblath]

The main motivation for this was to time file moving. This has now been implemented by itself in mover.go, taking away the main motivating factor. Priority is therefore reduced to low.