Code cleanup


Suffix.java:
In setIndexesTrusted() + setTrusted(), passed in the WriteableStorage.
In importPhaseOne(), used ExecutorService.submit() for single tasks rather than ExecutorService.invokeAll().
In TmpEnv.insert(), removed the AtomicBoolean, superseded by WriteableStorage.update() return value.
Renamed TmpEnv.isDNMatched() to contains() + handled null parameter.

Importer.java
Renamed idContainerMap and idECMap fields to indexIDToIndexMap and indexIDToECMap.