start left panel improvement

[wstolte]

no the items start unfolded. they may take too much space when more items are added

[luisrodriguezgalvez]

To do:

• No the items start unfolded.
• The categories become buttons (Input Data, Knowledge Base for Decissions and MSP Zoning)
• Only the subcategories of one category are visible at a time (i.e. cannot see subcategories of Input Data and MSP Zoning at the same time, only those subcategories of the active category)
• Fill Input Data with the same subcategories as Helcom Basemap

Take left menu of https://basemaps.helcom.fi/ as example