Add settings link to plugins page

[Brugman]

Description of the change

Adds a link to the Rollbar settings page on the plugins page. This way, after activation, you won't have to browse all menus, you just click the settings link and find out.

Type of change

• New feature (non-breaking change that adds functionality)

Related issues

None.

Checklists

I'm not yet familiar with testing, I did test manually of course, and I'm on Windows. I hope you'll take this without testing, or can run tests on my behalf.

[Brugman]

Awesome! I'll change the syntax. I copy pasted this and forgot to adapt it to the existing code style.