Extend keyword picker directive to support displaying all the suggested values when there is a selected value.

[josegar74]

By default typeahead, filters the list with the selected value.

To display all the suggested values configure the directive with the attribute data-show-hints-on-focus="true"

 <field xpath="/*/gmd:identificationInfo/*/gmd:resourceConstraints/*[gmd:accessConstraints]/gmd:otherConstraints"
                 del="../.."
                 use="data-gn-keyword-picker">
            <directiveAttributes data-thesaurus-key="external.theme.httpinspireeceuropaeumetadatacodelistLimitationsOnPublicAccess-LimitationsOnPublicAccess"
                                 data-display-definition="true"
                                 data-show-hints-on-focus="true"
                                 data-thesaurus-concept-id-attribute="xlinkCOLONhref"/>
          </field>

Some comments:

• The directive doesn't seem to work fine, at least with Anchors as the text value is lost on save, but it happens without the changes in this pull request. Something to review.

• It requires to change typeahead, maybe can be extended the prototype with the custom _onFocused, without having to modify the library. To investigate further.

[fxprunayre]

For me it works fine with Anchor

               <gmd:otherConstraints>
                  <gmx:Anchor xlink:href="http://inspire.ec.europa.eu/metadata-codelist/LimitationsOnPublicAccess/INSPIRE_Directive_Article13_1a">
public access limited according to Article 13(1)(a) of the INSPIRE Directive</gmx:Anchor>
               </gmd:otherConstraints>

and when adding show-hints-on-focus option the list is displayed