Css is needlesly bundled in hslayers code

[raitisbe]

Bug

Describe the bug Styles (bootstrap, whhg, hslayers) should not be included in main.js file, because it makes it hard to track why the components are so large in source-map-explorer, the styles are distributed with the application even if the container application developer chooses to use other font icons or his own bootstrap bundle.

Expected behavior Styles should be distributed outside hslayers bundle in separate files under node-modules/hslayers-ng/src/css/

Should provide also a compiled css file apart from scss.

[raitisbe]

Before:

After:

The bootsstrap code is only moved to another file, but ol.css is not imported twice now.