Ensure that --log is always used during obabel minimization.

Running a obabel minimization with a clean config and before
showing the forcefield configuration dialog would not add --log
to the options, and no progress was shown.

Change-Id: Ifc597659e71c7cf98158d885a6e48617180bcef0
Merge topic 'obabel-minimize-log' into master

3365ea12 Ensure that --log is always used during obabel minimization.