Add reload command and loading status

[StardustDL]

Problem

When config loading failed, it won't give any information to fix it.

Solution

• Show loading log when failed to load
• Add reload command to reload config without restarting.

Alternative

• Add loading log to debug data and use debug command to show it
• Add log data(?)
  • Add verbose option for log

[eXceediDeaL]

Finished. Add these features:

• reload command
• --verbose option
• logging support (not full)
• debug --log to show logs