First Alpha Release

This is a first pre-release that allows other people to test the Language Server. Don't expect anything to work.

Features at this time:

• Connect to IDEs and text editors over stdio
• Connect to remote clients over websocket or http
• Sync document content with the client
• Support plain PromQL queries
• Support queries inside yaml files
• Connect to a prometheus instance to get label and metric data
• Show error messages for incorrect queries in the client
• Show documentation on hover
  • Type information
  • Function documentation
  • Operator documentation
  • Metric and label help strings from a prometheus instance
  • Even when the Query has syntax errors
• Completion
  • Functions
  • Metrics
  • Labels
  • Context sensitive, i.e respecting function argument types
  • Even when the Query has syntax errors
• Signature information for functions (while typing)
• (Linting)
• (Formatting)