add docs

doc for inverted topN metric spec
a few more cleanups to docs
Merge pull request #646 from metamx/inverted-topn-metric-spec-docs

add docs
fix config with broker select and add docs
Merge branch 'master' of github.com:metamx/druid
a few slight tweaks and bumping up curator version
add query priorities to metric emission
completely async request proxying + jetty update
remove debug code
unnecessary arguments
fix compilation error
Merge pull request #647 from metamx/better-async

completely async request proxying + jetty update
fix index out of bounds
Cleaning up code sample indentations
Adding a section to detail supporting Kafka 8
rewrite router async logic
Merge pull request #650 from r4j4h/master

Adding Kafka 8 instructions to Loading Your Data tutorial docs to complement the existing Kafka 7 instructions
less verbose logging for LQP
Merge branch 'master' of github.com:metamx/druid
add back metrics