Add custom modal to plugin helpers (#2631)

Add custom modal to plugin helpers (#2631)

* Add custom modal component

* Add custom modal to app and plugins helpers

* Fixes custom modal component

* Add doc for custom modal

* Fix newline end of file html and scss files

* Move my-custom-modal component outside component for UserLoggedIn modals

* Move initializeCustomModal to ngAfterViewInit()

* Wrap events and conditionnals

* Replace ng-show with ngIf*

* Add modalRef to open only one modal + onCloseClick

* Refacto + Fix access methods of custom modal

* Fix methods names custom-modal.component

* Fix implement AfterViewInit & no default boolean

Co-authored-by: kimsible <kimsible@users.noreply.github.com>