diff: add synonyms for -M, -C, -B

Add new long-form options --detect-renames[=<n>], --detect-copies[=<n>],
and --break-rewrites[=[<n>][/<m>]] as synonyms for the -M, -C, and -B
options (respectively).

Signed-off-by: Kevin Ballard <kevin@sb.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/Documentation/diff-options.txt b/Documentation/diff-options.txt
index e745a3c..df37ccd 100644
--- a/Documentation/diff-options.txt
+++ b/Documentation/diff-options.txt
@@ -207,9 +207,11 @@
 	digits can be specified with `--abbrev=<n>`.
 
 -B::
+--break-rewrites[=[<n>][/<m>]]::
 	Break complete rewrite changes into pairs of delete and create.
 
 -M::
+--detect-renames[=<n>]::
 ifndef::git-log[]
 	Detect renames.
 endif::git-log[]
@@ -220,6 +222,7 @@
 endif::git-log[]
 
 -C::
+--detect-copies[=<n>]::
 	Detect copies as well as renames.  See also `--find-copies-harder`.
 
 ifndef::git-format-patch[]