Update CP2K tutorial with additional resources

Added section on useful tools and links for CP2K.

Author: alexvakimov

soft_and_tuts/3.1-cp2k.html

@@ -196,9 +196,15 @@
   &END SUBSYS
 &END FORCE_EVAL
 ```
+
+## D. Useful tools and links:
+
+  - [cp2k-basis](https://www.cp2k.org/tools:cp2k-basis): nice Basis-set-exchange-like website where you can select the basis sets 
+  and pseudopotentials for given elements and it would generate the input snippet for that.
 </xmp>
 
 
   <script type="text/javascript" src="https://cdn.rawgit.com/Naereen/StrapDown.js/master/strapdown.min.js"></script>
   </body>
 </html>
+