Reverted the idea of separate index/search analyzers.

Turns out this is not necessary as wildcard queries are not analyzed by
the Lucene query parser, so there's no risk of accidentally stripping
out the wildcards.
Made it possible to use different analyzers for different fields.

Use the defaultAnalyzer setting under fieldInfo and the analyzer setting
for each metadata field to configure. Currently only the values
"DEFAULT" (BLDutchAnalyzer), "nontokenizing" (BLNonTokenizingAnalyzer),
"whitespace" (BLWhitespaceAnalyzer) and "standard" (BLStandardTokenizer)
are supported, but more can easily be added in the future.
Re-used analyzer instances in Searcher.
Report canonical instead of absolute path in logs and error msgs.