Add initial documentation
Spark's project page (https://www.igniterealtime.org/projects/spark/documentation.jsp) currently only have a very limited readme, license and changelog (along with a wiki based user guide). Should also have a documentation about installation, maybe also mention SSL, SSO and other stuff (at least in the form of links to the forum). This will also be included with the source.
Having a list of supported XEPs would also be nice.
Documentation has been placed in a thread in Discourse and slowly will be updated. Closing this ticket as there won't be need to update it in the source.
As documentation's folder on the site is only updated during release, it is inconvenient to keep up to date documentation. Until this has changed to using the latest documentation in source, i'm moving everything to a forums post and linking to it on site.