Before updating, please note: Your old config files are not compatible. There have been so many changes that you'll probably have to go through the learning process again when configuring the plugin. Hopefully the learning curve is less steep this time, since I've improved the documentation and simplified the configuration. You'll have to upgrade everything, nothing is compatible. New connector, new addons, new everything.

Changelog:
- Improved config sync: It is now faster and can sync any file on the entire server. The interval is now configurable and there is a command to manually sync.
- Added support for 1.15
- Fixed bug where players could take items out of the menu
- Fixed enchantments
- Added support for all effects instead of just speed and invisibility
- New teleport action
- New firstavailableserver action: Teleports to the first available server in a list of servers. A server is available when it is online and online players < max players
- Actions can now be configured per section (separate actions for online, offline dynamic)
- Sponge connector now supports addons
- Player specific placeholders support
- Allow adding custom commands and items separate from menus (commands/items that can run any action)
- Restructured configuration files for more flexibility
- New java API for getting server status and registering custom actions
- No more console spam from connector messages. You can now check pinging status using /ssx status and /ssxc status
- Added command to view placeholders: /ssxc placeholders
- Allow creating multiple menus with the same title
- Added give delay option so it can work with plugins that annoyinly clear the player's inventory on join
- Opening the menu from another plugin no longer breaks it
- Added /ssx lagdebug command
- Connector addons are files instead of folders making it less annoying to install
- Instead of not opening the menu, the plugin will now send you a nice message in chat telling you what is wrong (in most cases)
- Fixed duplication bug when cancel-item-drop was turned on
- Fixed cancel-item-move not working for offhand in legacy version
- New connected: section that is active when you are currently connected to that server
- The server that is used for placeholders has been made independent from actions
- All SSX server placeholders are registered as PlaceholderAPI placeholders
- Removed /ss alias to avoid conflict with silkspawners
- SSX-Connector can now send player specific placeholders!
- All effects are supported now, instead of just invisibility and speed (as action and on join)
- Action to play sound
- Action to execute another action with a delay
- New randomserver: action
- New roundrobinserver: action
- Set commands to run after config sync
- Support for heads with custom textures
- Set custom item NBT (only ints, strings, bools, no compounds/lists)
- Addons are now reloaded using /ssxc reload
- Configurable cooldown for item clicking and command executing with configurable message
- Don't require a restart when adding new commands
- Added /ssx lagdebug and /ssx itemdebug
- Dependency updates