Outdated instructions how to open the console

[xMartin]

The instructions how to open the console in Google Chrome seem to be outdated, not matching the current user interface of the browser any more.

[arky]

@xMartin I can take a shot at this.

[xMartin]

Some improvements applied. Still a few TODOs:

• Check keyboard shortcuts: Should it be "alt" instead of "option"? Also it's now called "macOS"
• Update German translation

[xMartin]

A few more thoughts:

• We should consider to focus on the description how to open the tools with the mouse and possibly remove keyboard shortcuts completely. They are still confusing and no big help.
• We should add screenshots how to open the tools
• The description should not call the whole thing "console" but really "Developer Tools" as they are named by Chrome. This would also avoid confusion with the actual "console" tab of the Developer Tools which is also mentioned.