GreetMe || customize your server join/leaving message

Added: 1- A toggle button added to turn firework on/off. 2- Title feature added: a customizable title with hex color support displays on player's screen upon joining. Option to disable it available. 3- Sub-title option added, configurable and can be turned on/off. 4- Title fade-in, display time, and fade-out can be adjusted via config. 5- Sound option added: a customizable Minecraft sound plays upon player join. Option to disable it available. 6- PlaceholderAPI is now a soft-depend. Fixes: 1- Bugs fixed. 2- General plugin optimization.