Always update the url bar

[mlsteele]

Update the url on every change to the tree. This way you can just share the url immediately instead of having to open 'Options' and click 'Link'. I found this more convenient when collaborating as well as saving trees for later use.
I had to switch to using location.hash instead of location.search so that the browser doesn't reload.

Cheers,

• Another Miles S.

[mshang]

In principle, I agree with this change, however I think it would be too noisy to always have it on because

1. the URL is messy
2. users would have trouble understanding that they could just copy-paste the base.
   How about we replace the button with a toggle that defaults to off. When it's on, the address bar will have the full link.