Complete refactor of project file structure

Fix incorrect handing of default node parameters in SSD subscription.
Fix unable to parse some Clash rule-providers (#289).
Fix not filtering inline comments in some Surge rulesets. (#285)
Add Cron task options.
Add clean context option for persisting a JS context across the whole request.
Replace JS engine with QuickJS.

base/pref.example.ini

@@ -244,6 +244,11 @@ clash.log_level=info
 /v2ray=/sub?target=v2ray
 /trojan=/sub?target=trojan
 
+[tasks]
+;Tasks to be run regularly during server execution.
+;Format: Name`Cron_Expression`JS_Path`Timeout_in_seconds
+;task=tick`0/10 * * * * ?`tick.js`3
+
 [server]
 ;Address to bind on for Web Server
 listen=0.0.0.0