Initial version for profiling code
Refactoring profiling
profiles: add cleanup listener

This is to work around potential leaks in Tomcat.

Signed-off-by: Pierre-Alexandre Meyer <pierre@mouraf.org>
Return profiling json data as a new header
Merge branch 'profiling' of github.com:killbill/killbill into profiling
Profiling filters
Additional level of granularity for profilind DAO
Fix NPE in profiling code
Address one of the issue in #215

If we for instance change plan on the same date, we could end up with adding two fixed items when generating the new invoice items.
The fix will only keep the latest one by using a map to override previuous entry for the same date (and for the same subscription)
Hardening of the code after running integration tests:
- Fix NPEs that occured when invoice retrives the billing events associated with an account when a subscription start date is in the future (e.g transfer EOT)
- Fix Glitches with dates by ensuring that context createdDate -- used quite extensively in invoice code would be set in UTC, and therefore localDate ends up where we expect it to be.
- Change default setting for payment PluginDispatcher timeout from 90sec -> 5sec