next step: create udp/ip network packet header

This is needed, for example, when attaching a slave to a PCIe bridge.

needs proper implementation, this is just a scratchpad of code snippets.

- file name mess resolved
- unsing only type of WB interface

TODO: update software interface

Ignore lowest two address bits => can read over JTAG.

Renamed the methods from "proxy" to "wrap" for clarity.

Rename: begin -> addr_first
Rename: end   -> addr_last
Rename: component -> sdb_component

We will need this in the future and best to get all the ABI breakage at once.

Added versioning based on git history instead of svn keywords.