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

Documentation/git-cat-file.txt

@@ -9,8 +9,14 @@ git-cat-file - Provide content or type and size information for repository objec
 SYNOPSIS
 --------
 [verse]
-'git cat-file' (-t [--allow-unknown-type]| -s [--allow-unknown-type]| -e | -p | <type> | --textconv | --filters ) [--path=<path>] <object>
-'git cat-file' (--batch[=<format>] | --batch-check[=<format>]) [ --textconv | --filters ] [--follow-symlinks]
+'git cat-file' <type> <object>
+'git cat-file' (-e | -p) <object>
+'git cat-file' (-t | -s) [--allow-unknown-type] <object>
+'git cat-file' (--batch | --batch-check) [--batch-all-objects]
+	     [--buffer] [--follow-symlinks] [--unordered]
+	     [--textconv | --filters]
+'git cat-file' (--textconv | --filters)
+	     [<rev>:<path|tree-ish> | --path=<path|tree-ish> <rev>]
 
 DESCRIPTION
 -----------