Update link to plugin.xml specification in README.md (#92)

diff --git a/README.md b/README.md
index 81c533c..02ec64b 100644
--- a/README.md
+++ b/README.md
@@ -31,7 +31,7 @@
 
 ## Plugin Specification
 
---> [Available on docs.cordova.io](http://cordova.apache.org/docs/en/3.0.0/plugin_ref_spec.md) <--
+--> [Available on docs.cordova.io](http://cordova.apache.org/docs/en/latest/plugin_ref/spec.html) <--
 
 ## Quickstart