Fix JSON links

[jampukka]

Issue is that window.location.href already contains the window.location.search causing duplicated search part

Simplify JSON link construction in all files to just append (?|&)f=json to window.location.href based on search being empty (then ?) or not (then &). This should additionally fix JSON links when using any other query parameters (?filter= or ?api-key=<key> for example).
Not ideal still, if current search already contains value for query param f then this won't work, but that basically requires the user to manually enter ?f=html, which shouldn't really happen.

Should fix #160

[nls-jajuko]

I've used URL search parameters to modify location in hakunapi-html-npm-openlayers

f.ex.

const params = (new URL(document.location)).searchParams;
	  params.set('crs',selectedCrsURI);
	  document.location.search = params.toString(); 	 

hakunapi-html-npm-openlayers has some other packaging and distribution build tree shaking issues though.
It's a bit heavy to load at the moment.

[jampukka]

That's a lot better, I'll change all of these to use that pattern.

[jampukka]

This seems to work with everything I throw at it