Added transfer progress reporting for push and pull commands.

Added a new '-p' switch to the 'push' and 'pull' commands that outputs
the file transfer progress (bytes transmitted, total bytes, and % done).
This provides useful feedback when transferring large files, and also
makes it possible for other tools to easily monitor the progress of a
forked push/pull command.

Change-Id: Iee6f42f5bd41292e5bc80fba779f526f0072e356