Browser-laptop: Tor "new identity" button should be more user-friendly

[diracdeltas]

Test plan

1. Open a PT and enable Tor and visit any site
2. Shields-> Should show an option for new circuit for this site
3. Open a PT with Tor disabled and visit any site
4. Shields-> Should not show an option to load new circuit for the site
   

Currently it always appears as enabled regardless of whether there's a tor private tab open and just says "new identity"

maybe this can be moved to the popup that appears when you click on the urlbar lock icon instead of a global menu item

[riastradh-brave]

Tor Browser puts this under the Tor onion button in the address bar, alongside 'new circuit for this site' and a few other things.

[darkdh]

maybe we can have a button next to home button

[diracdeltas]

i think it should either go in siteInfo or shields so we can avoid more buttons in the UI

[diracdeltas]

shields probably makes more sense since it will basically be our equivalent of torbutton once we have the tor shields feature

[riastradh-brave]

For posterity: We moved it under shields, and made clean reload create a new circuit too.

[srirambv]

Verified on Windows 10 x64 using

• 0.23.11 - 6565c06
• Muon - 7.1.0
• libchromiumcontent - 67.0.3396.87

Verified on macOS 10.13.4 x64 using the following build:

• 0.23.12 88f6f0767c05ba5c4793ec2430a5cd742092fa6d
• muon: 7.1.1
• libchromiumcontent: 67.0.3396.87

Verified on Ubuntu 17.10 x64

• 0.23.14 - f4da85553f32e2c31539bab6cfbf32619ef0a936
• Muon - 7.1.1
• libchromiumcontent - 67.0.3396.87

[Keridoo]

As an ordinary Tor user, I strongly dislike "new identity" button has been move to the menu on the right hand side. I would like to have at least the option to move it elsewhere by using "Customize...".