Add cleantime to vs list

[allmightyspiff]

slcli vs list should display a nice time format. Basically just run the value through utils.cleantime and that should do the trick.

The createDate column should be passed through utils.clean_time() to generate a nice and readable formatted time string.

slcli vs list is a little complicated, my suggestion would be to add a lambda function to the COLUMNS definition that looks like this.

    column_helper.Column(
        'createDate',
        lambda guest: utils.clean_time(guest.get('createDate'))),

The column_helper class basically lets you define a column name and map it to a API result, or in this case, define a function to transform the data whenever its added to the table.