Better provisioning, get rid of hard-coded dir.

Provisioning has been improved and now is idempotent; also used bundle
with the ==deployment option not to tamper with systems; also made the
root dir of the software installation depend on an env variable called
BASEDIR. If basedir is not defined, the the CWD is used instead.

Change-Id: I5e467cdce4ee59e1a0ce0d5f50f7242e570a18c6
Signed-off-by: Giuseppe Lavagetto <glavagetto@wikimedia.org>