Upgraded to Tehuti 0.5

Tehuti 0.5 includes a fix about Histograms not clearing their samples properly. Also added some trace logging code in StoreStats.
Releasing Voldemort 1.8.14
Fix bitrot and make it build again with newer toolchain
Fix the lib.private section of pkg-config file
Merge pull request #208 from readams/master

Fix bitrot and make it build again with newer toolchain
Slop for delete operations

Problems:
1) Exception handling of delete is very different at 4 places ( on
normal response, required failure, quorum failure) and after pipeline is
finished.
2) The exceptions are reported again and again ( They are not removed
from the map).
3) Some places ignore obsoleteVersionException, some others report it.
4) There is a zombie state abort, there is no way to reach this state.
5) Multiple slops could be sent, because of the issue 2. When the
pipeline is aborted, no slops could be sent.

Solution:
Defined a common method, so that all 4 places call into the same method.
Only the condition for calling is different. Race conditions still
exist, after zone failure check but before pipeline finishes the
exception will go missing, slops will not happen, but the chances are
reduced.
Got rid of the state PerformDeletedHintHandoff as
QuotaExceededExceptions will not be reported as failures. Now doing it
in place.
deletes InvalidMetadata is not handled correctly

Previously the InvalidMetadata exception was just reported, but the pipeline did not abort and retry.
Now if the pipeline is not finished it will abort and retry, otherwise just reported.
Delete requests do not abort on InvalidMetadataException

Parallel deletes do not abort the pipeline immediately on InvalidMetadata requests.
Now after receiving an terminal error from handleResponseError the execute method
returns so the pipeline processor will abort further processing.
Quota store fixes

1) Refactored QuotaLimitingStore test to add delete test cases
2) Combined the PUT and GET quotas into 2 quotas.
Do slops for delete only if zone&quorum succeededs

Previously Slops are sent, irrespective of Zone & Quorum status
Now Slops are sent only when the quorum succeeds.
operationCompleted is not set in some code paths

Now it is set in all code paths. Reduced warning of the error to info
level as it is not a very useful error to report in warning level.