Extended the fetchFile() method of the ComposerRepository class to be
able to deal with http basic auth. In case the remote resource responds
with a 401 ask the user for access credentials and retry quering the
resource again.
Moved 401 handling from ComposerRepository to RemoteFilesystem and
displaying the url when asking for the credentials.
Reverted the last changes. Changed logic in callbackGet() method to
respect the 401 handling also if STREAM_NOTIFY_FAILURE fires as on my
local machine the handling of STREAM_NOTIFY_AUTH_REQUIRED never got
executed.
Removed dead statement.
Merge remote-tracking branch 'bitExpert/feature/repo_basic_auth'