* commands/configfile.c (grub_cmd_source): New function.
(GRUB_MOD_INIT): Register the commands `source' and `.'.
(GRUB_MOD_FINI): De-register the commands `source' and `.'.
* commands/configfile.c (grub_cmd_configfile): Execute the
configfile within its own context.
* include/grub/env.h (grub_env_context_open): New prototype.
(grub_env_context_close): Likewise.
* kern/env.c (grub_env): Removed.
(grub_env_sorted): Likewise.
(grub_env_context): New variable.
(grub_env_var_context): Likewise.
(grub_env_find): Search both the active context and the global
context.
(grub_env_context_open): New function.
(grub_env_context_close): Likewise.
(grub_env_insert): Likewise.
(grub_env_remove): Likewise.
(grub_env_export): Likewise.
(grub_env_set): Changed to use helper functions to avoid code
duplication.
(grub_env_iterate): Rewritten so both the current context and the
global context are being used.
* normal/command.c (export_command): New function.
(grub_command_init): Register the `export' function.
* commands/cat.c (GRUB_MOD_INIT): Use better documentation.
(grub_cat_init): Likewise.
* loader/i386/pc/chainloader_normal.c (GRUB_MOD_INIT): Likewise.
(options): Likewise.
* commands/configfile.c (GRUB_MOD_INIT): Likewise.
(grub_configfile_init): Likewise.
* font/manager.c (GRUB_MOD_INIT): Likewise.
* commands/help.c (GRUB_MOD_INIT): Likewise.
(grub_help_init): Likewise.
* normal/command.c (grub_command_init): Likewise.
* loader/i386/pc/linux_normal.c (GRUB_MOD_INIT): Likewise.
* disk/loopback.c (grub_loop_init): Likewise.
(GRUB_MOD_INIT): Likewise.
* commands/ls.c (grub_ls_init): Likewise.
(GRUB_MOD_INIT): Likewise.
(options): Likewise.
* commands/boot.c (grub_boot_init): Likewise.
(GRUB_MOD_INIT): Likewise.
* loader/i386/pc/multiboot_normal.c (GRUB_MOD_INIT): Likewise.
* commands/i386/pc/reboot.c (grub_reboot_init): Likewise.
(GRUB_MOD_INIT): Likewise.
* commands/cmp.c (grub_cmp_init): Likewise.
(GRUB_MOD_INIT): Likewise.
* normal/arg.c: Use <> instead of "" to include header files.
(SHORT_ARG_HELP): New macro.
(SHORT_ARG_USAGE): Likewise.
(help_options): Specify SHORT_ARG_HELP and SHORT_ARG_USAGE instead
of 'h' and 'u' for help and usage, respectively. Use more GNU-like
descriptions.
(find_short): Check if C is 'h' or 'u' explicitly.
(grub_arg_show_help): Use space characters instead of tabs. Treat
SHORT_ARG_HELP and SHORT_ARG_USAGE exceptionally so that -h and -u
are shown with --help and --usage only if they are not used for
the command itself.
(parse_option): Use SHORT_ARG_HELP and SHORT_ARG_USAGE instead of
'h' and 'u'.
* include/grub/arg.h (struct grub_arg_option): Add the qualifier
const into "longarg". Change the type of "shortarg" to int.
