config.txt: move gpg.* to a separate file

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Documentation/config.txt

@@ -341,26 +341,7 @@ include::config/gitweb.txt[]
 
 include::config/grep.txt[]
 
-gpg.program::
-	Use this custom program instead of "`gpg`" found on `$PATH` when
-	making or verifying a PGP signature. The program must support the
-	same command-line interface as GPG, namely, to verify a detached
-	signature, "`gpg --verify $file - <$signature`" is run, and the
-	program is expected to signal a good signature by exiting with
-	code 0, and to generate an ASCII-armored detached signature, the
-	standard input of "`gpg -bsau $key`" is fed with the contents to be
-	signed, and the program is expected to send the result to its
-	standard output.
-
-gpg.format::
-	Specifies which key format to use when signing with `--gpg-sign`.
-	Default is "openpgp" and another possible value is "x509".
-
-gpg.<format>.program::
-	Use this to customize the program used for the signing format you
-	chose. (see `gpg.program` and `gpg.format`) `gpg.program` can still
-	be used as a legacy synonym for	`gpg.openpgp.program`. The default
-	value for `gpg.x509.program` is "gpgsm".
+include::config/gpg.txt[]
 
 include::gui-config.txt[]
 

Documentation/config/gpg.txt

@@ -0,0 +1,20 @@
+gpg.program::
+	Use this custom program instead of "`gpg`" found on `$PATH` when
+	making or verifying a PGP signature. The program must support the
+	same command-line interface as GPG, namely, to verify a detached
+	signature, "`gpg --verify $file - <$signature`" is run, and the
+	program is expected to signal a good signature by exiting with
+	code 0, and to generate an ASCII-armored detached signature, the
+	standard input of "`gpg -bsau $key`" is fed with the contents to be
+	signed, and the program is expected to send the result to its
+	standard output.
+
+gpg.format::
+	Specifies which key format to use when signing with `--gpg-sign`.
+	Default is "openpgp" and another possible value is "x509".
+
+gpg.<format>.program::
+	Use this to customize the program used for the signing format you
+	chose. (see `gpg.program` and `gpg.format`) `gpg.program` can still
+	be used as a legacy synonym for	`gpg.openpgp.program`. The default
+	value for `gpg.x509.program` is "gpgsm".