Support latest IntelliJ

Changelog

This release supports the newest version of IntelliJ

Switch to gradle (Fixes #3 )
Update to lsp4j 0.9.0

Compatibility

Requires IntelliJ 2019.2+
Supports IntelliJ 2020.2 EAP

Installation

• Choose IntelliJ >> Settings >> Plugins >> SettingsIcon >> Install Plugin from Disk... and Select MagpieBridgeLSPSupport.zip.
• Restart IntelliJ.