DRILL-5089: Dynamically load schema of storage plugin only when needed for every query
For each query, loading all storage plugins and loading all workspaces under file system plugins is not needed.
This patch use DynamicRootSchema as the root schema for Drill. Which loads correspondent storage only when needed.
infoschema to read full schema information and load second level schema accordingly.
for workspaces under the same Filesyetm, no need to create FileSystem for each workspace.
use fs.access API to check permission which is available after HDFS 2.6 except for windows + local file system case.
Add unit tests to test with a broken mock storage: with a storage that will throw Exception in regiterSchema method,
all queries even on good storages shall fail without this fix(Drill still load all schemas from all storages).
(cherry picked from commit a66d1d7)
