Make creating configurations easier

Proposal:
Make the influx config create command interactive for parameters not passed as flags

Current behavior:
You must pass all config parameters as command line arguments, which requires knowing what arguments you need

Desired behavior:
A user should be able to run influx config create alone and be promoted to input each config parameter.

Alternatives considered:
You could allow a mix of command line arguments and interactivity, only prompting for what wasn't passed on the CLI.

You could also check for environment variables to use as default options in the interactive mode.

Use case:
Using configurations is the new recommended way to use the influxdb CLI, but the process for creating them is not clear or intuitive, which will leave new users feeling confused by InfluxDB and having an undesirably high "time to awesome"

Start with the influx config create command entry point and determine how its current required parameters are defined and collected. Compare interactive prompting with the proposed mixed flag-and-prompt and environment-variable alternatives; done means running influx config create without flags prompts for each required configuration parameter.