pkg: remove support for autoload (automatically loading package at start). * pkg.m, pkg/private/install.m, pkg/private/load_packages.m, pkg/private/rebuild.m: remove support for automatically loading packages. Having octave itself and the package manager automatically load packages is a bad idea. If a user wants to load a package at startup then it should specify it on its octaverc file. This can also be done on the system-wide octaverc file. This also simplifies pkg (this patch only removes code). * startup/version-rcfile: do not run 'pkg ("load", "auto")' at startup. * doc/interpreter/package.txi: remove mention of package autoload from the manual.

--- a/scripts/pkg/private/load_packages.m	Thu Apr 14 10:27:07 2016 +1000
+++ b/scripts/pkg/private/load_packages.m	Sun Apr 10 23:00:07 2016 +0100
@@ -36,15 +36,6 @@
   ## Load all.
   if (length (files) == 1 && strcmp (files{1}, "all"))
     idx = [1:length(installed_pkgs_lst)];
-  ## Load auto.
-  elseif (length (files) == 1 && strcmp (files{1}, "auto"))
-    idx = [];
-    for i = 1:length (installed_pkgs_lst)
-      if (exist (fullfile (pdirs{i}, "packinfo", ".autoload"), "file"))
-        idx(end + 1) = i;
-      endif
-    endfor
-  ## Load package_name1 ...
   else
     idx = [];
     for i = 1:length (files)