Add search engine and quick search for repositories (#1727)

Add a powerful search engine based on lucene to the scm-manager api.
The api can be used to index objects, simply by annotating them and add them to an index.
The first indexed object is the repository which could queried by quick search in the header.

scm-ui/ui-components/src/forms/FilterInput.tsx

@@ -81,7 +81,7 @@ const FilterInput: FC<Props> = ({ filter, value, testId, placeholder, autoFocus,
           autoFocus={autoFocus || false}
         />
         <span className="icon is-small is-left">
-          <i className="fas fa-search" />
+          <i className="fas fa-filter" />
         </span>
       </div>
     </form>