Co-authored-by: Robert Lange <robert.lange@uni-leipzig.de>

- The preferred ebook format parameter must be passed when requesting full text to ensure the correct link is returned.

- This makes the [SearchTabsFilters] mechanism in config.ini work with EDS; further effort would be needed to add global hidden filter support similar to that found in searches.ini.

- Allows console commands to utilize themes without Laminas-MVC.

- Also adds support for hidden fields and initing form with extra parameters.

Co-authored-by: Samuli Sillanpää <samuli.sillanpaa@helsinki.fi>

- Resolves VUFIND-1392

- Refactor template and renderer determination in content controller
- Add TemplateBased ContentBlock for embedding static content in other contexts
- Includes improved test coverage

- Adds a mechanism for defining local Grunt tasks.

* Slot helper prototype.

- Slot/block system for easier customization.
- Designed to set block values then include parent template (helper coming).
- start/end for buffer capture.
- set for string setting.
- clear for value clearing.

* Add get method to Slot.

* Add Slot method documentation.

* Improve Slot documentation.

* Change syntax to slot('name')->action(). Fix instancing.

* Improve documentation.

* Add examples to slot PR.

* Update documentation.

* checkstyles

* Fix error with slot->get.

* Remove trim so any value type can be saved.

* Add prepend/append methods to slots.

* Move Slots helper to VuFindTheme.

* Add unit tests for Slot helper.

* Clear Slot prepends and appends.

* Space and trim block output.

* checkstyle typo

* Improve documentation of non-string slot values.

* Add method constants.

* Add __invoke(name, val) and __toString shortcuts.

* Clarify prepend/append concatination.

* Slot clear returns old contents.

* Update test to match new clea...