Adding [allow|deny]_addresses settings to yaml config file

[eastebry]

Pretty straightforward - adding the allow/deny command line arguments to the config loader so they can be included in a yaml configuration. This allows you to have a yaml config that looks like this:

ip: "127.0.0.1"
port: 8888

deny_ranges:
  - 93.0.0.0/8 

allow_addresses:
  - 93.184.215.14

allow_ranges:
  - 192.168.0.0/16

deny_addresses:
  - 192.168.1.5

I also opened a separate issue (#236) when playing around with this configuration, and discovering that the allow/deny configurations don't work as I would expect. This doesn't make a difference for this PR though.

[jjiang-stripe]

This seems pretty reasonable to me! It's nice to be able to apply these settings via a YAML config instead of only CLI

[coveralls]

Pull Request Test Coverage Report for Build 11412454683

Warning: This coverage report may be inaccurate.

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Details

• 0 of 8 (0.0%) changed or added relevant lines in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage decreased (-0.2%) to 54.353%

---

Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
pkg/smokescreen/config_loader.go	0	8	0.0%

Totals
Change from base Build 11384028862:	-0.2%
Covered Lines:	1436
Relevant Lines:	2642

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💛 - Coveralls