doc: add docs for module.paths

PR-URL: https://github.com/nodejs/node/pull/14435
Refs: https://github.com/nodejs/node/issues/14371#issuecomment-317184131
Reviewed-By: Vse Mozhet Byt <vsemozhetbyt@gmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Khaidi Chu <i@2333.moe>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Refael Ackermann <refack@gmail.com>
Reviewed-By: Tobias Nießen <tniessen@tnie.de>
Reviewed-By: Gibson Fahnestock <gibfahn@gmail.com>

doc/api/modules.md

@@ -768,6 +768,15 @@ added: v0.1.16
 
 The module that first required this one.
 
+### module.paths
+<!-- YAML
+added: v0.4.0
+-->
+
+* {string[]}
+
+The search paths for the module.
+
 ### module.require(id)
 <!-- YAML
 added: v0.5.1