raise FailedShardsException instead of NoShardAvailableActionException

returns a more descriptive error message to the user and is
consistent with the failures from the Search/Get Tasks
update changes to reflect release of 0.38.4
fix: log error instead of recurring exception throwing if shard of orphaned partition is started
parser: add "alter table add column" support
implemented `sys.shards.orphan_partition` expression
Merge branch 's/orphan-partition-expression'
fixed substr scalar doctest
fix flaky tests
upgraded elasticsearch to 1.1.2
fixed failing tests because of ES 1.1.2 upgrade: index.version.created
Merge pull request #865 from crate/l/update-es

L/update es
handle CollectionTerminatedException correctly in handleNodeCollect()
fix flaky tests

these tests expected that with refresh_interval=-1 new rows are only visible
when a refresh is triggered externally, but it can be triggered internally at any point, no guarantees
Merge pull request #870 from crate/m/flaky_refresh_tests

fix flaky tests
update docs for refresh_interval setting
ensure that a _version=0 query has no match

and does not execute
Merge pull request #873 from crate/m/refresh-docs

update docs for refresh_interval setting
update docs about group by and aggregates
Merge pull request #874 from crate/m/group_by_docs

update docs about group by and aggregates
change substring function to handle null values correctly