Fixes many, though not all 64bit-warnings. In lots of places, pointers are
cast to ints to be then used as array subscripts. The only way to deal with
this is to change them to long. Additionally, use calloc() to allocate the
int_array in istr.c and drop the (wrong) macro patch to istr.h. Should make
dtbuilder work on 32bit again.
Added proper SharedDtSvcReqs in lnxLib.tmpl and CplusplusLibC in
linux.cf. This allows the libstdc++ dependancy to be properly
declared for libDtSvc so that it is not neccessary to hardcode 'CCLINK
= g++' in the Imakefiles of programs linking angainst libDtSvc.