We were using "search_index_file" as the variable for the search index, when this really was a directory and not a file. It's been renamed to "search_index_dir." We handle backwards-compatibility of the variable name so as not to break people who have specified a custom path, but this also means that existing configurations with this pointing to the global Review Board install directory will also be migrated. Users will have to deal with this if they want to use search.

Our old default for this variable was a directory inside the installed package directory, which was very wrong. We now point to a "search-index" directory in the site directory, which we also create for them in rb-site.

This also updates things to allow for relative paths.

None yet. I don't have a working PyLucene setup here, but I'd like to get a pair of eyes on this first.