maint: Clean up m-files before Octave 8.1 release. * external.txi, oop.txi, Table.h, documentation.cc, gui-preferences-ed.h, lo-specfun.cc, range.tst : Eliminate triple newlines. * Map.m, MemoizedFunction.m, delaunayn.m, inputParser.m, __publish_latex_output__.m, publish.m, unpack.m, fminbnd.m, __add_default_menu__.m, gammainc.m, gallery.m, hadamard.m, weboptions.m: Add newline after keyword "function" or before keyword "endfunction" for readability. * getaudiodata.m, pkg.m : Add semicolon to end of line for error() statement. * movegui.m: Combine mutliple calls to set() into one for performance. * __unimplemented__.m (missing_functions): Remove missing functions that have been implemented. * __vectorize__.m, check_default_input.m, betaincinv.m, gammaincinv.m: Remove semicolon at end of line with "function" declaration. * weboptions.m: Remove semicolon at end of line with "if" keyword. * integrate_adaptive.m, factor.m: Use keyword "endif" rather than bare "end".