Merge branch 'ah/doc-empty-string-is-false'

Doc update.

* ah/doc-empty-string-is-false:
  doc: clarify "config --bool" behaviour with empty string

Documentation/git.txt

@@ -75,7 +75,8 @@ example the following invocations are equivalent:
 Note that omitting the `=` in `git -c foo.bar ...` is allowed and sets
 `foo.bar` to the boolean true value (just like `[foo]bar` would in a
 config file). Including the equals but with an empty value (like `git -c
-foo.bar= ...`) sets `foo.bar` to the empty string.
+foo.bar= ...`) sets `foo.bar` to the empty string which ` git config
+--bool` will convert to `false`.
 
 --exec-path[=<path>]::
 	Path to wherever your core Git programs are installed.