Updating code to handle event filters
1. Adding a new Inclusion FIlter
2. Added new Config property - isFilteredEventTypeIncluded
3. Updated code for stop processing for HDFS write if flush is disabled
pom.xml: guava is now required at compile time

Signed-off-by: Pierre-Alexandre Meyer <pierre@ning.com>
Resolving review comments
Merge branch 'collector-event-filter' of https://github.com/ning/collector into collector-event-filter