Moved NoTransporterException and NoRepositoryLayoutException into org.eclipse.aether.transfer package next to related NoRepositoryConnectorException

Introduced RepositoryLayoutFactory SPI and made basic repo connector use it to retrieve layout

Renamed TransportRequest to TransportTask etc. (requests usually have results, the Transporter methods are void so request/result doesn't really fit)

Introduced aether-transport-file and dropped aether-connector-file

Introduced module aether-transport-wagon and dropped aether-connector-wagon

Introduced aether-transport-classpath module hosting a ClasspathTransporterFactory

Introduced new TransporterFactory SPI along with a new basic connector building on top of it

Introduced TransferEvent.Builder.resetType() to ease generation of event sequence for a given transfer