Marker click behaviour and fixes

[teemutontti]

Laji.fi data

• Fixed the structure of the data coming from the API fetch
• Filtered out unnecessary incomplete data

CustomMarker

• Changed to use endangermenStatus-prop to determine which marker to render
• Takes in children-prop primarily used for rendering Popup-component

MapComponent

• Holds the state for sightings data and passes the setter to MapBounds.tsx and the list to SpeciesLayer.tsx

ObservationPopup and SightingPopup

• Custom Popup-components for viewing observation and sighting data

Other changes:

• Added custom marker images to assets-folder
• Fixed issue where map clicks weren't going through the Controls-container and Fabs-stack
• Limiting the fetching of sighting data

Todos:

• Create different styling for sighting and observation marker clusters
• Disable fetching when clicking markers are clicked (see issue #84)