Allow NetBox client to skip SSL certificate Verification

[MaxAnderson95]

This adds an additional argument to the NetBoxClient class constructor called verify which specifies whether to verify the authenticity of the SSL certificate presented by the NetBox server. The default remains True like it already is today.

The value of verify is passed to the constructor of RestClient where it is added as an attribute to the underlying Session automatically.

[adamhemsley]

Hey, I manually implemented your change as it is exactly what I was looking for, and it worked perfectly many thanks!

It's a shame no-one from the project appears to be around. It's a bit surprising given this is linked from the official pages. It's starting to make me regret using this module..