CLI table styles (rebased onto develop)



This is the same as gh-2353 but rebased onto develop.

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Add `--style={csv,sql,plain}` option to a number of CLI commands:
 * [ ] `bin/omero hql`
 * [ ] `bin/omero ldap list`
 * [ ] `bin/omero group list`
 * [ ] `bin/omero user list`
For each, the default is the previous style, "--style=sql". 

The styles `csv` and `plain` (which is `csv` minus headers) should be easier for parsing in a script. Hopefully useful for testing and similar as well.

To test, check that each command continues to work with each of the three options. Further, suggestions for API additions/modifications are encouraged.

/cc @manics @sbesson @knabar @pwalczysko @ximenesuk