Cleanup, removed out-commented code of old json editor
Fixed php recipe to display errors
Todo added for module config
Moved header/footer from the default/landing layout templates to layout partials
Refactoring of partials related to the landing page and the json editor.

 * base url fix -> leading slash added to css/js libs
 * html elements (title, buttons, ...) removed from jsoneditor partial
 * to
 * make it more generic
 * renamed some partials and moved them to a better place
Moved an angular app script and introduced a guideline how angular apps should be defined
Readme add for the layout template files
New twig filter implemented: jol_without_gist which encodes 'something' to a javascript object literal by removing the gist field
Using the jsoneditor partial in the endpoint/edit template
Moved the json editor section from the endpoint/index template to a partial
Added app script for the endpoint/edit page and added support for a noscript configuration of the json editor
Refactoring of sass files. Layout and page sass files are distinguished.

View partials are shared but in some cases different pages using the same
partial need a different set of css rules. The two types, 'layout' and
'page', allow a clear separation.