maint: Replace some uses of goto in libinterp. * ls-mat4.cc (read_mat_file_header): Replace "goto data_read_error" with "return -1". * ls-mat4.cc (read_mat_binary_data): Replace "goto data_read_error" with direct call to error. Move variable declarations to point of usage. * ls-mat5.cc (read_mat5_tag, write_mat5_tag): Replace "goto data_read_error" with "return 1". * ls-mat5.cc (save_mat5_binary_element): Replace "goto skip_to_next" with "return true". * ls-oct-binary.cc (read_binary_data): Replace "goto data_read_error" with direct call to error. * mex.cc (valid_key): Replace "goto done" with "return retval". * rand.cc (do_rand): Clarify comment. * pt-binop.cc (tree_binary_expression::rvalue1): Replace "goto done" with "return octave_value (xxx)" * pt-binop.cc (tree_boolean_expression::rvalue1): Replace "goto done" with "return octave_value (xxx)"

To cite GNU Octave in publications use:

  John W. Eaton, David Bateman, Søren Hauberg, Rik Wehbring (2015).
  GNU Octave version 4.0.0 manual: a high-level interactive language for
  numerical computations.
  URL http://www.gnu.org/software/octave/doc/interpreter/

A BibTeX entry for LaTeX users is:

  @book{,
    author    = {John W. Eaton, David Bateman, S\oren Hauberg, and Rik Wehbring},
    title     = {{GNU Octave} version 4.0.0 manual: a high-level interactive language for numerical computations},
    year      = {2015},
    url       = {http://www.gnu.org/software/octave/doc/interpreter},
  }

We have invested a lot of time and effort in creating GNU Octave, please cite it
when using it.  See also `citation pkgname' for citing Octave packages.