* jh/alias-i18n:
  completion: fix zsh alias listing for subsection aliases
  alias: support non-alphanumeric names via subsection syntax
  alias: prepare for subsection aliases
  help: use list_aliases() for alias listing

The example showing the equivalence between alias.last and
alias.last.command was missing the list continuation marks (+
between the shell session block and the following prose, leaving
the paragraph detached from the list item in the rendered output.

Signed-off-by: Jonatan Holmgren <jonatan@jontes.page>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

When git-config stores a key of the form alias..name, it records
it under an empty subsection ([alias ""]). The new subsection-aware
alias lookup would see a non-NULL but zero-length subsection and
fall into the subsection code path, where it required a "command"
key and thus silently ignored the entry.

Normalize an empty subsection to NULL before any further processing
so that entries stored this way continue to work as plain
case-insensitive aliases, matching the pre-subsection behaviour.

Users who relied on alias..name to create an alias literally named
".name" may want to migrate to subsection syntax, which looks less confusing:

    [alias ".name"]
        command = <value>

Add tests covering both the empty-subsection compatibility case and
the leading-dot alias via the new syntax.

Signed-off-by: Jonatan Holmgren <jonatan@jontes.page>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

The list_aliases() function sets the util pointer of each list item to
a heap-allocated copy of the alias command value.  Two callers failed
to free these util pointers:

 - list_cmds() in git.c collects a string list with STRING_LIST_INIT_DUP
   and clears it with string_list_clear(&list, 0), which frees the
   duplicated strings (strdup_strings=1) but not the util pointers.
   Pass free_util=1 to free them.

 - list_cmds_by_config() in help.c calls string_list_sort_u(list, 0) to
   deduplicate the list before processing completion.commands overrides.
   When duplicate entries are removed, the util pointer of each discarded
   item is leaked because free_util=0.  Pass free_util=1 to free them.

Reported-by: Jacob Keller <jacob.e.keller@intel.com>
Signed-off-by: Jonatan Holmgren <jonatan@jontes.page>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Add missing list continuation marks ('+') after code blocks and shell examples
so paragraphs render correctly as part of the preceding list item.

Signed-off-by: Jonatan Holmgren <jonatan@jontes.page>
Signed-off-by: Junio C Hamano <gitster@pobox.com>