Added monero.how statistics link, as suggested by moneromoo

knowledge-base/user-guides/monero_tools.md

@@ -23,3 +23,5 @@ These tools can be used to gain information about the Monero network or your tra
 ###[Monero offline wallet generator](http://moneroaddress.org/)
 
 ###[Monero network mixin statistics](http://moneroblocks.info/stats)
+
+###[Monero.how statistics](https://www.monero.how/)