Define extensions to keep and discuss extraction into own repository

[erdlet]

This issue shall be a base for defining extensions we want to keep maintained by the Krazo team. Also it has to be discussed, if some or all extensions will be moved into a separate repository to reduce maintenance effort in the Krazo repository and to focus on the development of Krazo Core.

To get a quick overview over our extensions and the status of the underlaying template engine, I'll add a list here so we can discuss about them.

@eclipse-ee4j/ee4j-krazo-committers please comment here if there is an extension that must be kept or, on the other hand, can simply be deleted in your opinion

Edit: These are all engines supported by an extension with some additional info which may help to decide how to proceed.

Extension	Template engine	latest version	ext. version	jakarta namespace?	comments	maintainer
asciidoc	asciidoctorj	2.5.4	2.5.2	yes	---	---
freemarker	freemarker	2.3.31	2.3.31	yes	---	---
jade	jade4j	1.3.2	1.3.2	yes	looks abandoned and has vulnerabilities	---
mustache	mustache.java	0.9.10	0.9.10	yes	---	---
pebble	pebble	3.1.5	3.1.5	yes	---	---
stringtemplate	ST4	4.3.1	4.3.3	yes	---	---
thymeleaf	Thymeleaf	3.1.0.M1	3.1.0.M2	yes	---	@erdlet
velocity	velocity	2.3	2.3	yes	---	---
handlebars	handlebars	4.3.0	4.2.0	no	looks not regularly updated	@jcputney
jetbrick	jetbrick	2.1.10	2.1.10	no	looks abandoned.	---
jinjava	jinjava	2.6.0	2.6.0	no	PR for jakarta namespace open but needs attention	---

[jcputney]

We use the Handlebars extension, so if you need a maintainer, I might be able to take that on.

[erdlet]

Thanks for your feedback @jcputney :) Would be great if you take care of this extension.

[erdlet]

I added a table with information about all extensions and the used template engines.

[erdlet]

Jade4J is now pug4j. So I'll remove the Jade4J extension and, if someone wants to use it, an new extension for pug4j needs to be created.

[erdlet]

The extensions are migrated to krazo-extensions. This issue will be closed after #328 is merged.

[ivargrimstad]

I think we should consider keeping asciidoc (depending on the amount of maintenance required). Not that it is necessarily much used right now, but it provides a migration path if someone wants to move e.g. gh-pages with asciidoc or similar down the road

[erdlet]

I think we should consider keeping asciidoc (depending on the amount of maintenance required). Not that it is necessarily much used right now, but it provides a migration path if someone wants to move e.g. gh-pages with asciidoc or similar down the road

I migrated all plugins except Jade and Jetbricks :)