InfluxDB Publisher v1: Add support for HTTPS connection

[BrianJKoopman]

Description

This PR adds support for connecting to InfluxDB over HTTPS, adding the ability to set the ssl and verify_ssl arguments, which get passed to the InfluxDBClient object.

It also passes these new arguments (and the new credentials implemented in #431) to the client object whenever the connection is lost and the agent tries to reconnect.

Motivation and Context

SSL support was requested in #430 (reply in thread).

How Has This Been Tested?

I have not tested SSL support, but have tested with the default False arguments, and HTTP connections continue to work.

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.

[BrianJKoopman]

Tested with an HTTPS connection in #430 (reply in thread). Merging.