add variable »config« to the template

as a central point to contain our template variables for easier passing
add missing quotes around array key
improve highlighting

also take into account multi-value query fields for highlight queries, just as for the main query fields
create the template variable config containing a number of the previously scattered variables

at the top level there now remain:

* [settings]
* arguments
* config
* results
* document[-previous|-next[-number]] (for detail action)
* suggestions (for suggest action)

The Partials and Templates are adapted accordingly.
germania-sacra: clean up and comment TypoScript configuration
remove f:debug from SelectFacet partial