Custom scripting, #song=, translations

- A song can be linked directly by adding "#song=<id>" to the url, replace `<id>` with the id in the database, after loading it jumps immediately jumps to the difficulty selection
- Added tutorial translations
- Fixed song preview not playing
- Use text fallback for the logo when there are no vectors
- Increased combo cache by 1 pixel
- A custom javascript file can be loaded from config.json by defining "custom_js" value
- Added lots of events to help writing custom js files: `version-link, title-screen, language-change, song-select, song-select-move, song-select-difficulty, song-select-back, about, about-link, tutorial, import-songs, import-songs-default, session, session-start, session-end, debug, load-song, load-song-player2, load-song-unfocused, load-song-cancel, load-song-error, game-start, key-events, p2-game-end, p2-disconnected, p2-abandoned, pause, unpause, pause-restart, pause-song-select, game-lag, scoresheet, scoresheet-player2`
- Event syntax example:
```js
addEventListener("game-start", event => {
	console.log("game-start", event.detail)
})
```

public/src/js/p2.js

@@ -58,6 +58,7 @@ class P2Connection{
 					this.open()
 				}
 			}, 500)
+			pageEvents.send("p2-disconnected")
 		}
 		var addedType = this.allEvents.get("close")
 		if(addedType){
@@ -111,6 +112,11 @@ class P2Connection{
 				break
 			case "gameend":
 				this.otherConnected = false
+				if(this.session){
+					pageEvents.send("session-end")
+				}else if(!this.results){
+					pageEvents.send("p2-game-end")
+				}
 				this.session = false
 				if(this.hashLock){
 					this.hash("")
@@ -122,6 +128,7 @@ class P2Connection{
 				for(var i in response.value){
 					this.results[i] = response.value[i].toString()
 				}
+				pageEvents.send("scoresheet-player2", this.results)
 				break
 			case "note":
 				this.notes.push(response.value)