[patch] Add add-auto-load-scripts-directory

[Joel Brobecker]

I agree it makes sense to have a command to appent to the current
scripts path.

> gdb/
> 2014-11-13  Jan Kratochvil  <jan.kratochvil@redhat.com>
> 
> 	Add add-auto-load-scripts-directory.
> 	* NEWS (Changes since GDB 7.8): Add add-auto-load-scripts-directory.
> 	* auto-load.c (add_auto_load_dir): New function.
> 	(_initialize_auto_load): Install it.

The code part of the patch are approved.

> gdb/doc/
> 2014-11-13  Jan Kratochvil  <jan.kratochvil@redhat.com>
> 
> 	Add add-auto-load-scripts-directory.
> 	* gdb.texinfo (Auto-loading): Add add-auto-load-scripts-directory link.
> 	(objfile-gdbdotext file): Add add-auto-load-scripts-directory.

-- 
Joel