GH-427 SCP client: fix DefaultScpClient.upload(InputStream, ...)
GH-455 Fix BaseCipher: make sure all bytes are processed
GH-470 MontgomeryCurve: synchronize access to KeyPairGenerator
GH-489 SFTP v3 client: better file type determination
PR-472 sshd-spring-sftp: fix client start
PR-476 Fix Android detection
PR-486 Add missing equals and hashCode to U2F key classes
SSHD-1237 Handle keep-alive channel requests
SFTP read operations now check the amount of data they get back. If it's more than requested an exception is thrown. SFTP servers must never return more data than the client requested, but it appears that there are some that do so. If property SftpModuleProperties.TOLERATE_EXCESS_DATA is set to true, a warning is logged and such excess data is silently discarded.