4.0.0

In this release the backend was updated to v4.0.0

Breaking Changes

• Added ticksVisible to TimeScaleOptions, renamed drawTicks to ticksVisible in PriceScaleOptions
• Added methods:
  • SeriesApi.markers
  • SeriesApi.dataByIndex

Fixes

• Not possible to create a BaseValuePrice object (#46)
• Markers are not displaying in the demo (#44)
• Fix crash on multiple subscribe (#57)