Make chrome-devtools:// URLs clickable

node.js now allows [debugging via chrome dev tools ](https://nodejs.org/api/debugger.html#debugger_v8_inspector_integration_for_node_js). To do it, you should call node with `--inspect`. After that node prints URL looking like `chrome-devtools://devtools/bundled/inspector.html...`, which should be opened in google chrome to debug the script.

It would be convinient to click it and open in the browser (without copying it by hands).
Looks like it can be done by adding `chrome-devtools:` to [this line](https://github.com/Guake/guake/blob/master/src/guake/terminal.py#L55). Am I right?

Perhaps, there should be an option to set custom URL schemes in configuration?