- Add fpga_scrap_R[W].
- Change fpga_mask_R to fpga_mask_RW

This function should be moved to the base class.
On error it prints out the LOFAR device type, i.e. "SDP"m which
is set in the first lines of the class.

The Tango C++ kernel provides a built-in function init().  Unfortunately
are names in Tango (mostly) case-insensitive.  This led to a name clash
with our own Init() function and at first unexplainable behaviour.

The logic was backwards since it was tested if a condition was
not given.  Instead the logic should follow what the wrapper name
suggests:  test if the device is in a state or if the device is in
state on.

Refactor for Paulus' pypcc2 version with arrays

See merge request !2

State management

See merge request !1