doc: Periodic grammarcheck of documentation. * doc/interpreter/contrib.txi, doc/interpreter/expr.txi, doc/interpreter/func.txi, doc/interpreter/linalg.txi, doc/interpreter/plot.txi, libinterp/corefcn/data.cc, libinterp/corefcn/debug.cc, libinterp/corefcn/graphics.cc, libinterp/corefcn/help.cc, libinterp/corefcn/load-save.cc, libinterp/corefcn/profiler.cc, libinterp/corefcn/syscalls.cc, libinterp/corefcn/utils.cc, libinterp/corefcn/variables.cc, libinterp/dldfcn/__init_fltk__.cc, scripts/general/deal.m, scripts/help/__gripe_missing_component__.m, scripts/miscellaneous/desktop.m, scripts/pkg/private/default_prefix.m, scripts/plot/appearance/__getlegenddata__.m, scripts/plot/util/pan.m, scripts/plot/util/rotate.m, scripts/plot/util/rotate3d.m, scripts/plot/util/zoom.m, scripts/signal/periodogram.m, scripts/specfun/factor.m, scripts/specfun/primes.m, scripts/statistics/base/lscov.m, scripts/testfun/private/compare_plot_demos.m, scripts/testfun/private/dump_demos.m, scripts/testfun/private/html_compare_plot_demos.m, scripts/testfun/test.m: Periodic grammarcheck of documentation.

--- a/scripts/plot/util/rotate3d.m
+++ b/scripts/plot/util/rotate3d.m
@@ -21,15 +21,16 @@
 ## @deftypefnx {Command} {} rotate3d on
 ## @deftypefnx {Command} {} rotate3d off
 ## @deftypefnx {Function File} {} rotate3d (@var{hax}, @dots{})
-## Control 3D rotation mode of interactive graph in GUI.
+## Control 3-D rotation mode of interactive graph in GUI.
 ##
 ## The function state input may be either @qcode{"on"} or @qcode{"off"}
-## and can only be set for 3D plots.
+## and can only be set for 3-D plots.
 ##
 ## If the first argument @var{hax} is an axes handle, then operate on
 ## this axis rather than the current axes returned by @code{gca}.
 ##
 ## To query the current mode use the @code{get} function.  For example:
+##
 ## @example
 ## mode = get (gca, "rotate3d");
 ## @end example