[BUG] verbosity and debug logging not working in versions 7.x

[mickotronic]

Describe the bug
If setting verbosity for eventgen in inputs.conf in versions 7.x, eventgen-main.log does not contain anything.
This same configuration would result in debug log output to eventgen-main.log in versions 6.x.
There is no documentation that I can find that describes how to attain the same level of debug logging in versions 7.x, so I am making this a bug as it's unexpected behaviour and an undocumented change.

To Reproduce
Steps to reproduce the behavior:

1. In eventgen v6.5.3, set verbosity to 10 or 40 in local inputs.conf. Restart splunk.
2. Confirm eventgen-main.log contains debug log entries.
3. Remove eventgen v6.5.3 and install version 7.0.
4. Use same configuration for verbosity.

Expected behavior
eventgen-main.log contains debug information.

Actual behavior
On versions 7.x, eventgen-main.log is empty. In some cases it logs errors.

Screenshots

Sample files and eventgen.conf file

Do you run eventgen with SA-eventgen?
Yes

If you are using SA-Eventgen with Splunk (please complete the following information):

• OS: Tested on Centos 7 and Solus Linux
• Browser Firefox
• Eventgen Version 7.x (tested all versions in 7.x branch).
• Splunk Version 8.0.5
• What other apps you have installed in Splunk etc/apps?

If you are using eventgen with pip module mode (please complete the following information):

• python version: [e.g. 2.6]
• OS: [e.g. Windows10]
• Virtual Env is used: Yes/No
• Eventgen Version [e.g. 6.3.2]

Additional context
Add any other context about the problem here.