feat: add plugin data bio entities (MIN-224)

Closes MIN-224

Objective:

• implement bio entities data methods for plugins

What has been done:

• getAllChemicals method
• getAllContent method
• getAllDrugs method
• getAllMarkers method
• getShownElements method
• clearAllElements method
• addSingleMarker method
• removeSingleMarker method
• removeAllMarkers method
• rendering of pin/surface markers
• unit tests

Example plugin (some buttons may not work as methods names has changed)