[Buster-Client] Forces use of primary monitor on multi monitor setup

**System**
* OS name: Windows
* OS version: 10 Pro build 1809
* Browser name: Chrome
* Browser version: 74.0.3729.131 (Official Build) (64-bit)

**Extension**

* Extension version: 0.5.2
* User input simulation: yes
* Client app version: 0.2.0
* Client app installed successfully: yes

**Bug description**

When using User Input Simulation on multi monitor the client will get the browser's relative position from the correct monitor, but will place the cursor on the x and y offset of the OS's primary monitor.

IE: I have two monitors hooked up to my system, ML (left) and MR (right (primary)).
Chrome is open om ML and i trigger buster to do its magic. My cursor will move to MR, but will position itself relatively on the same position as where my browser/recaptcha dialog is, but it's on the wrong monitor.

Moving Chrome to MR will resolve this issue, but this forces me either to use a single monitor for Chrome, or drag it to MR whenever i want to let Buster do its thing

**Logs**
Browser:
```
N/A
```
Client app:
```
2019/05/14 10:20:36.323482 Starting client (version: 0.2.0)
2019/05/14 10:20:36.323482 Receiving message
2019/05/14 10:20:36.324483 Processing message
2019/05/14 10:20:36.324483 Command: ping
2019/05/14 10:20:36.324483 Sending response
2019/05/14 10:20:36.324483 Receiving message
2019/05/14 10:20:36.325483 Closing client
```

Start with the client app's user input simulation and the handling of browser-relative positions on Windows multi-monitor setups. Reproduce the issue with Chrome on a secondary monitor, then verify that the cursor is placed on the same monitor and at the corresponding position as the browser or reCAPTCHA dialog.

Written by the indexing model from the issue text.