fixed spelling in HostBridgeTest
HostBridgeTest always deletes the disk file on the host system

The check is not needed.
Implemented first set of tests for VDiskFileInputStream, VDiskFileOutputStream
fixed bug because of wrong understanding of the interface of OutputStream

Bug is covered by test case and was found this way.
Merge branch 'master' of https://github.com/groggi/eth-jcd