Merge branch 'ab/cat-file'

Assorted updates to "git cat-file", especially "-h".

* ab/cat-file:
  cat-file: s/_/-/ in typo'd usage_msg_optf() message
  cat-file: don't whitespace-pad "(...)" in SYNOPSIS and usage output
  cat-file: use GET_OID_ONLY_TO_DIE in --(textconv|filters)
  object-name.c: don't have GET_OID_ONLY_TO_DIE imply *_QUIETLY
  cat-file: correct and improve usage information
  cat-file: fix remaining usage bugs
  cat-file: make --batch-all-objects a CMDMODE
  cat-file: move "usage" variable to cmd_cat_file()
  cat-file docs: fix SYNOPSIS and "-h" output
  parse-options API: add a usage_msg_optf()
  cat-file tests: test messaging on bad objects/paths
  cat-file tests: test bad usage

parse-options.h

@@ -225,6 +225,16 @@ NORETURN void usage_msg_opt(const char *msg,
 			    const char * const *usagestr,
 			    const struct option *options);
 
+/**
+ * usage_msg_optf() is like usage_msg_opt() except that the first
+ * argument is a format string, and optional format arguments follow
+ * after the 3rd option.
+ */
+__attribute__((format (printf,1,4)))
+void NORETURN usage_msg_optf(const char *fmt,
+			     const char * const *usagestr,
+			     const struct option *options, ...);
+
 /*
  * Use these assertions for callbacks that expect to be called with NONEG and
  * NOARG respectively, and do not otherwise handle the "unset" and "arg"