Fix for storing non-unicode string types.
Moved description HTML generation to the frontend.

The backend now sends a configurable set of fields to the frontend in response to a description view request. The frontend produces suitable HTML from these fields.
Made config.mk for the frontend apply after the files settings variables; removed config.css.

There is no need for config.css now because you can add arbitrary CSS files in config.mk.
Factored out frontend description list generation code.
Comment in the frontend makefile to clarify how config.mk works.
Merge branch 'refactoringbuildindex' into avherald, and update the later accordingly.