Use C++11 nullptr rather than 0 in code (bug #51565). * mk-opts.pl, BlockArray.cpp, KeyboardTranslator.cpp, Screen.cpp, TerminalCharacterDecoder.cpp, TerminalView.cpp, Vt102Emulation.cpp, dialog.cc, find-files-dialog.cc, file-editor-tab.cc, main-window.cc, ls-hdf5.cc, oct-procbuf.h, oct-stream.cc, oct-tex-lexer.in.ll, zfstream.cc, ov-builtin.h, ov-fcn-handle.cc, ov-typeinfo.h, ov-usr-fcn.h, options-usage.h, lex.ll, oct-parse.in.yy, pt-loop.h, Array.cc, CSparse.cc, Sparse.h, dSparse.cc, fCMatrix.cc, idx-vector.cc, idx-vector.h, sparse-chol.cc, cmd-edit.cc, oct-sort.cc, main.in.cc: Use C++11 nullptr rather than 0 in code (bug #51565).

--- a/liboctave/numeric/sparse-chol.cc	Tue Jul 25 14:54:10 2017 -0700
+++ b/liboctave/numeric/sparse-chol.cc	Wed Jul 26 16:26:31 2017 -0700
@@ -269,7 +269,7 @@
       ac->nzmax = a.nnz ();
       ac->packed = true;
       ac->sorted = true;
-      ac->nz = 0;
+      ac->nz = nullptr;
 #if defined (OCTAVE_ENABLE_64)
       ac->itype = CHOLMOD_LONG;
 #else