doc: spellcheck of documentation before 3.8 release. * doc/interpreter/doccheck/aspell-octave.en.pws: Add new words to Octave-specific dictionary. * libinterp/corefcn/ellipj.cc, scripts/image/imfinfo.m, scripts/miscellaneous/copyfile.m, scripts/miscellaneous/movefile.m, scripts/plot/meshgrid.m, scripts/specfun/expint.m: spellcheck of documentation before 3.8 release.