Uses lower/uppercase in usual manner. Remove a debug statement.
alternative syntax \inputwikipage[<level>]{<pageid>[|Title]}

Metadata handling of this syntax is more robust, which should garanteed
better cache handling.
cached output, bit refactoring

Some refactoring
- move recursion counter to helper instance
- move header indention to helper instance
Improves #9 by eliminating some globals.
- remove bibliography stuff, and use only zotero bibliography helper
when building a zip
- set http headers via metadata, so that default export routine can be
used
- use cached latex output creation
   - the usecache check depends on the inserted pages
   - separated cachefiles for a page are created per header indent level
with which the page is included
update listitem_open signature
minor changes config syntax component
additional tests for new and old syntax

Not sure if caching of the old insert syntax works always correct.
Sometimes it succeed...