-Replace codes.h with iberror.h (or remove)
-Move gds__vax_integer and gds__event_block* to alt.cpp and isc_ to gds.cpp
-Use ISC_QUAD internally
-Use isc_vax_integer internally
placed some variables in context
fixed some function signatures
closed a few possible buffer overruns
sorry to the platform maintainers, I can't verify what I did for non-Win32 builds
Since we already have the define ISC_STATUS_LENGTH for the the length of
the status vector, we should use it! Replaced 'status[20]' with
'status[ISC_STATUS_LENGTH]'.
Replaced the different symbolic names for the maximum length of a path
(MAX_PATH, MAX_PATH_LENGTH, MAXPATHLEN) with one uniq symbol MAXPATHLEN.