0.12dev: Log traceback of exceptions raised during `trac-admin` commands and command completion.
0.12dev: Log traceback of exceptions raised during `trac-admin` commands and command completion.

Replaced `env_open()` by an `env` property in `TracAdmin`.


git-svn-id: 0d96b0c1a6983ccc08b3732614f4d6bfcf9cbb42@7941 af82e41b-90c4-0310-8c96-b1721e28e2e2

rbaumg/trac,rbaumg/trac,rbaumg/trac,rbaumg/trac