[PATCHv2] config: document blame configuration

[Stefan Beller <sbeller@google.com>]

The options are currently only referenced by the git-blame man page,
also explain them in git-config, which is the canonical page to
contain all config options.

Signed-off-by: Stefan Beller <sbeller@google.com>
---

 * correct option to blame.showRoot
 * camelCased other options
 * use linkgit:git-<command>[1] instead of `git-cmd` as that
   is correct, but maybe overused.
 * --date is `backticked` now.

 Documentation/config.txt | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/Documentation/config.txt b/Documentation/config.txt
index 1ac0ae6adb..ba0156b1e8 100644
--- a/Documentation/config.txt
+++ b/Documentation/config.txt
@@ -949,6 +949,23 @@ apply.whitespace::
 	Tells 'git apply' how to handle whitespaces, in the same way
 	as the `--whitespace` option. See linkgit:git-apply[1].
 
+blame.showRoot::
+	Do not treat root commits as boundaries in linkgit:git-blame[1].
+	This option defaults to false.
+
+blame.blankBoundary::
+	Show blank SHA-1 for boundary commits in linkgit:git-blame[1].
+	This option defaults to false.
+
+blame.showEmail::
+	Show the author email instead of author name in linkgit:git-blame[1].
+	This option defaults to false.
+
+blame.date::
+	Specifies the format used to output dates in linkgit:git-blame[1].
+	If unset the iso format is used. For supported values,
+	see the discussion of the `--date` option at linkgit:git-log[1].
+
 branch.autoSetupMerge::
 	Tells 'git branch' and 'git checkout' to set up new branches
 	so that linkgit:git-pull[1] will appropriately merge from the
-- 
2.15.0.7.g980e40477f