"playback://" protocol support for Windows

I've been looking to get 'playback://' support for windows running.
I tried compiling the project to a win32 package and adding the protocol to Windows using the following registry key:

```
REGEDIT4

[HKEY_CLASSES_ROOT\playback]
@="URL:playback Protocol"
"URL Protocol"=""

[HKEY_CLASSES_ROOT\playback\shell]

[HKEY_CLASSES_ROOT\playback\shell\open]

[HKEY_CLASSES_ROOT\playback\shell\open\command]
@="\"D:\\Node\\Projects\\playback-win32\\playback.exe" \"%1\""
```

This doesn't appear to work.
Clicking a magnet or playback:// link and trying to run it with the generated executable doesn't seem to be working on Windows. In both cases it just launches the splash screen, as where on OSX it would start streaming the related magnet link (or other media linked in playback://).

Edit:
I also tried adding the protocol manually to Firefox. When I select the .exe to launch the protocol with, it also simply starts the app without streaming.

Start by reproducing the generated win32 package with the shown registry entry and a playback:// or magnet link, then compare its launch behavior with the working OSX path. Done means launching through either protocol begins streaming the linked media instead of showing only the splash screen.

Written by the indexing model from the issue text.