Creating branch to work on new TinyMCE customs buttons
 - ADD New 'Pop' button to TinyMCE
 - CHANGE popup tag format to [popup=<title>,<link>]<content>[/popup]
ADD editor controller to manage TinyMCE custom button
CHANGE bootstrap.php include to add new editor controller.min.js
adding new test view & code for editor controller
ADD bootstrap-multiselect to bowser installer
ADD service for manage post content
CHANGE graphics for pnj and prv tag
Update jquery version to multiselect dependencies
CHANGE Extract constant string to constant variable
CHANGE change dependencies for PostContentService
CHANGE Extract JS from editor_tag_*.html.twig to JS controller/editor.js
CHANGE Do not render PNJ tag if PNJ doest not exist
ADD Adding editor/editor_squelette.html.twig to manage duplicate code for editor/editor_tag_*.html.twig
Merge tinymce button evolution