WIP
Add back presearcher query filtering

Running into OOMs with big documents on a couple of benchmarks, so lets bring
back prefiltering of the presearcher boolean queries.  But instead of building a
massive Set of tokens at commit time, we instead use a TermsEnum at query-build
time, which seems to be much more efficient.
Add a maxTermLength to SuffixingNGramTokenFilter

An incoming document contained a base64-encoded image in it, which resolved to a
30,000 byte long token.  This caused the SuffixingNGramTokenFilter to emit
several million tokens, resulting in OOM.  This commit adds a maximum termLength
to ngrammize, and anything over that length will simple have an ANYTOKEN
emitted.
Add TermWeightor implementation
DocumentTokenFilter.PASSTHROUGH got lost in a merge somewhere
Merge branch 'nrt' into termweights

Conflicts:
	src/main/java/uk/co/flax/luwak/presearcher/DocumentTokenFilter.java
	src/main/java/uk/co/flax/luwak/presearcher/TermFilteredPresearcher.java
	src/main/java/uk/co/flax/luwak/presearcher/WildcardNGramPresearcher.java
Add a ReportingWeightor to help with debugging
TermsEnumFilter should return EmptyTokenStream for non-searchable fields
Fix wildcard handling in TermFiltered and token length weighting
increase maxtoken size to 30 - 15 is way too low
RegexpNGramTermExtractor didn't deal with . and ? correctly

Was treating regexps as globs, oops.
javadocs
Matcher factories should be static final singletons
Remove presearcher document filtering

With weighting it's not necessary, and it's too easy to shoot yourself in the
foot with it.  If you don't want something considered for presearcher matching,
then lower its weight with a FieldWeightRule, or just don't include it in the
InputDocument.
WildcardNGramPresearcher should use Builder pattern

It's got enough parameters now to make the constructor confusing.
Set version to 1.1.0
Javadocs
Monitor.match() should take standard Collectors

No need to enforce that clients should pass a TimedCollector, we just do an
instanceof check after the search.
Javadocs
Add deleteById methods to monitor