Any generated headers go in $(BUILD)/genhdr/, and are #included as
'genhdr/xxx.h'.

The autogenerated header files have been moved about, and an extra
include dir has been added, which means you can give a custom
BUILD=newbuilddir option to make, and everything "just works"

Also tidied up the way the different Makefiles build their include-
directory flags

Small fixes to get it compiling with ARMCC.  I have no idea why
category_t was in the enum definition for qstrs...

Can now have null bytes in strings.  Can define ROM qstrs per port using
qstrdefsport.h