config.txt: move splitIndex.* 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

@@ -409,30 +409,7 @@ include::config/sequencer.txt[]
 
 include::config/showbranch.txt[]
 
-splitIndex.maxPercentChange::
-	When the split index feature is used, this specifies the
-	percent of entries the split index can contain compared to the
-	total number of entries in both the split index and the shared
-	index before a new shared index is written.
-	The value should be between 0 and 100. If the value is 0 then
-	a new shared index is always written, if it is 100 a new
-	shared index is never written.
-	By default the value is 20, so a new shared index is written
-	if the number of entries in the split index would be greater
-	than 20 percent of the total number of entries.
-	See linkgit:git-update-index[1].
-
-splitIndex.sharedIndexExpire::
-	When the split index feature is used, shared index files that
-	were not modified since the time this variable specifies will
-	be removed when a new shared index file is created. The value
-	"now" expires all entries immediately, and "never" suppresses
-	expiration altogether.
-	The default value is "2.weeks.ago".
-	Note that a shared index file is considered modified (for the
-	purpose of expiration) each time a new split-index file is
-	either created based on it or read from it.
-	See linkgit:git-update-index[1].
+include::config/splitindex.txt[]
 
 include::config/ssh.txt[]
 

Documentation/config/splitindex.txt

@@ -0,0 +1,24 @@
+splitIndex.maxPercentChange::
+	When the split index feature is used, this specifies the
+	percent of entries the split index can contain compared to the
+	total number of entries in both the split index and the shared
+	index before a new shared index is written.
+	The value should be between 0 and 100. If the value is 0 then
+	a new shared index is always written, if it is 100 a new
+	shared index is never written.
+	By default the value is 20, so a new shared index is written
+	if the number of entries in the split index would be greater
+	than 20 percent of the total number of entries.
+	See linkgit:git-update-index[1].
+
+splitIndex.sharedIndexExpire::
+	When the split index feature is used, shared index files that
+	were not modified since the time this variable specifies will
+	be removed when a new shared index file is created. The value
+	"now" expires all entries immediately, and "never" suppresses
+	expiration altogether.
+	The default value is "2.weeks.ago".
+	Note that a shared index file is considered modified (for the
+	purpose of expiration) each time a new split-index file is
+	either created based on it or read from it.
+	See linkgit:git-update-index[1].