Generic APB Master Stub for APB and APB3 Protocols

Generic APB master stub. Based on an AXI master stub and an AXI2APB bridge. Supports both APB and APB3 protocols (APB3 is with pready and pslverr signals). The design is built according to input parameters: address bits, protocol type, etc. The source files are written in RobustVerilog, a free RobustVerilog parser can be downloaded from http://www.provartec.comedatools