improve back button behavior

[andrewsu]

Steps to reproduce:

1. Start with https://smart-api.info/registry?q=tcga
   1. reports "Total APIs: 3" and shows three results
2. Click #gene -> https://smart-api.info/registry?q=tcga&tags=gene
   1. still reports "Total APIs: 3" (incorrectly), but only shows the two APIs with the gene tag (correctly)
3. Click back button
   1. reports same results as in Step 2 -- was expecting results as described in Step 1

[marcodarko]

I have improved the logic that handles history state changes to update the results with the current query on the url if you go back in history. Let me know if that solves this issue. While doing this I also noticed the Total APIs number was wrong because of this, so also made sure that reset and updated correctly.