Update shinystan site

Author: jgabry

_pkgdown.yml

@@ -57,7 +57,8 @@ articles:
 
 reference:
   - title: "Package overview"
-    desc:  "Details about the shinystan R package"
+    desc: > 
+      Details about the shinystan R package.
     contents: 
       - shinystan-package
   - title: "Launching the app"

favicon.ico

@@ -15,16 +15,18 @@
 <br> 
 <div style="text-align:center">
 <a href="http://mc-stan.org/assets/img/shinystan/home.png">
-<img src="http://mc-stan.org/assets/img/shinystan/home.png" width=19% />
+<img src="http://mc-stan.org/assets/img/shinystan/home.png" width=23.75% />
 </a>
 <a href="http://mc-stan.org/assets/img/shinystan/explore.png">
-<img src="http://mc-stan.org/assets/img/shinystan/explore.png" width=24.5% />
+<img src="http://mc-stan.org/assets/img/shinystan/explore.png" width=30.625% />
 </a>
 <a href="http://mc-stan.org/assets/img/shinystan/diagnose.png">
-<img src="http://mc-stan.org/assets/img/shinystan/diagnose.png" width=24.5% />
+<img src="http://mc-stan.org/assets/img/shinystan/diagnose.png" width=30.625% />
 </a>
 </div>
 
+<br>
+
 ShinyStan provides immediate, informative, customizable visual and
 numerical summaries of model parameters and convergence diagnostics for
 MCMC simulations. The ShinyStan interface is coded primarily in R using