builtin/show-ref: explicitly spell out different modes in synopsis

The synopsis treats the `--verify` and the implicit mode the same. They
are slightly different though:

    - They accept different sets of flags.

    - The implicit mode accepts patterns while the `--verify` mode
      accepts references.

Split up the synopsis for these two modes such that we can disambiguate
those differences.

While at it, drop "--quiet" from the pattern mode's synopsis. It does
not make a lot of sense to list patterns, but squelch the listing output
itself. The description for "--quiet" is adapted accordingly.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Documentation/git-show-ref.txt

@@ -8,9 +8,12 @@ git-show-ref - List references in a local repository
 SYNOPSIS
 --------
 [verse]
-'git show-ref' [-q | --quiet] [--verify] [--head] [-d | --dereference]
+'git show-ref' [--head] [-d | --dereference]
 	     [-s | --hash[=<n>]] [--abbrev[=<n>]] [--tags]
 	     [--heads] [--] [<pattern>...]
+'git show-ref' --verify [-q | --quiet] [-d | --dereference]
+	     [-s | --hash[=<n>]] [--abbrev[=<n>]]
+	     [--] [<ref>...]
 'git show-ref' --exclude-existing[=<pattern>]
 
 DESCRIPTION
@@ -70,8 +73,8 @@ OPTIONS
 -q::
 --quiet::
 
-	Do not print any results to stdout. When combined with `--verify`, this
+	Do not print any results to stdout. Can be used with `--verify` to
-	can be used to silently check if a reference exists.
+	silently check if a reference exists.
 
 --exclude-existing[=<pattern>]::
 

builtin/show-ref.c

@@ -11,9 +11,12 @@
 #include "parse-options.h"
 
 static const char * const show_ref_usage[] = {
-	N_("git show-ref [-q | --quiet] [--verify] [--head] [-d | --dereference]\n"
+	N_("git show-ref [--head] [-d | --dereference]\n"
 	   "             [-s | --hash[=<n>]] [--abbrev[=<n>]] [--tags]\n"
 	   "             [--heads] [--] [<pattern>...]"),
+	N_("git show-ref --verify [-q | --quiet] [-d | --dereference]\n"
+	   "             [-s | --hash[=<n>]] [--abbrev[=<n>]]\n"
+	   "             [--] [<ref>...]"),
 	N_("git show-ref --exclude-existing[=<pattern>]"),
 	NULL
 };