PraseTja: Add branches

- Needs the following changes to the database: change `easy`, `normal`, `hard`, and `oni` to `TEXT` type
- When adding songs to the database and if, for example, a song's 7-star difficulty has a branch, instead of `7` input `7 B`, this is to display song's branch support on the song selection
- Branch can be forced in debug

public/src/js/importsongs.js

@@ -199,7 +199,7 @@
 				songObj.subtitle = songObj.subtitle_en = subtitle
 				songObj.preview = meta.demostart ? Math.floor(meta.demostart * 1000) : 0
 				if(meta.level){
-					songObj.stars[this.courseTypes[diff]] = meta.level
+					songObj.stars[this.courseTypes[diff]] = meta.level + (meta.branch ? " B" : "")
 				}
 				if(meta.wave){
 					songObj.music = this.otherFiles[dir + meta.wave.toLowerCase()]