DatabaseRef -> AsyncDatabaseHelper
AsyncDatabaseHelper improved
various cleanups

Iterable -> TypedIterable
custom timeout -> standard timeout
provider protocol and domain refactored
DatasetManager implementation started
AsyncSQLUpdateClause implemented
Failure message handling added
DatasetManager update
equals/hashCode added
DatasetManager improved
FutureUtils simplified

Result class removed
flatResult -> flatMap, result -> map
AsyncDatabaseHelper variables renamed
FutureUtils removed from AsyncDatabaseHelper
sequence added
collect -> map/flatMap if possible
result.toString() output added to failure message
mapValue implemented
DatasetManager formatted
transactionality fix