Add timeout to waiting bin/omero admin commands (Fix #10361)

All commands which use `waitup` and `waitdown` internally now
take a `--wait` parameter (in seconds).
try/finally after store.attach to close sessions (Fix #9331)
Raise Exception() on Ice-mismatch (Fix #10346)

Duplicate the check from `omero/plugins/admin.py` in
`omero/clients.py` so that trying to create a client object
fails.
Remove print statements
Move version check to omero/__init__.py
Revive Ice import in clients.py
Merge pull request #826 from joshmoore/py-cli-fixes

Python & CLI fixes