git-remote-helpers.txt: document invocation before input format

In the distant past, the order things were documented was
'Invocation', 'Commands', 'Capabilities', ...

Then it was decided that before giving a list of Commands, there
should be an overall description of the 'Input format', which was
a wise decision. However, this description was put as the very
first thing, with the rationale that any implementor would want
to know that first.

However, it seems an implementor would actually first need to
know how the remote helper will be invoked, so moving
'Invocation' to the front again seems logical. Moreover, we now
don't switch from discussing the input format to the invocation
style and then back to input related stuff.

Signed-off-by: Max Horn <max@quendi.de>
Acked-by: Sverre Rabbelier <srabbelier@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
git-remote-helpers.txt: document missing capabilities

Specifically, document the 'export' and '(im|ex)port-marks'
capabilities as well as the export command, which were
undocumented (but in active use).

Signed-off-by: Max Horn <max@quendi.de>
Acked-by: Sverre Rabbelier <srabbelier@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
git-remote-helpers.txt: minor grammar fix

Signed-off-by: Max Horn <max@quendi.de>
Acked-by: Sverre Rabbelier <srabbelier@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
git-remote-helpers.txt: rearrange description of capabilities

This also remove some duplication in the descriptions
(e.g. refspec was explained twice with similar level of detail).

Signed-off-by: Max Horn <max@quendi.de>
Acked-by: Sverre Rabbelier <srabbelier@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
git-remote-helpers.txt: clarify command <-> capability correspondences

In particular, document 'list for-push' separately from 'list', as
the former needs only be supported for the push/export
capabilities, and the latter only for fetch/import. Indeed, a
hypothetically 'push-only' helper would only need to support the
former, not the latter.

Signed-off-by: Max Horn <max@quendi.de>
Acked-by: Sverre Rabbelier <srabbelier@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
git-remote-helpers.txt: clarify options & ref list attributes

The documentation was misleading in that it gave the impression that
'for-push' could be used as a ref attribute in the output of the
'list' command. That is wrong.

Also, explicitly point out the connection between the commands
'list' and 'options' on the one hand, and the sections
'REF LIST ATTRIBUTES' and 'OPTIONS' on the other hand.

Signed-off-by: Max Horn <max@quendi.de>
Acked-by: Sverre Rabbelier <srabbelier@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
git.txt: add missing info about --git-dir command-line option

Unlike other environment variables (e.g. GIT_WORK_TREE,	GIT_NAMESPACE),
the Documentation/git.txt file did not mention that the GIT_DIR
environment variable can also be set using the --git-dir command line
option.

Signed-off-by: Manlio Perillo <manlio.perillo@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Merge branch 'mh/doc-remote-helpers'

* mh/doc-remote-helpers:
  git-remote-helpers.txt: clarify options & ref list attributes
  git-remote-helpers.txt: clarify command <-> capability correspondences
  git-remote-helpers.txt: rearrange description of capabilities
  git-remote-helpers.txt: minor grammar fix
  git-remote-helpers.txt: document missing capabilities
  git-remote-helpers.txt: document invocation before input format
Fix sizeof usage in get_permutations

Currently it gets the size of an otherwise unrelated, unused variable
instead of the expected struct size.

Signed-off-by: Matthew Daley <mattjd@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Merge branch 'maint'