docs(guidelines): add missing step

RELEASING.md

@@ -24,6 +24,7 @@ Implications:
 3. Login: `npm adduser`
 4. Add dist-tag: `npm dist-tag add ng-table@n.n.n latest`
     * where `n.n.n` is the version of the package that you now want to make the latest
+5. Remove the pre-release tag from the github release of this version
 
 
 ## Documentation
@@ -33,4 +34,4 @@ To publish updates to the library documentation site:
 1. `npm run doc`
     * this will re-generate the api-Docs
 2. `npm run doc-deploy`
-    * this will prublish the content of demo-site directory from this repo into the gh-pages branch
+    * this will prublish the content of demo-site directory from this repo into the gh-pages branch