updating mergo.Merge() to version passing override functions

[spellgen]

I started building an sdk myself, based on crypt because mod rewrite was broken on my target system.
Now that that back-end is fixed I'd rather use the published API paths and am happy to have found your package.
I noticed that you had pinned it to an old version of mergo - offering a small PR to update your call to their current format for mergo.Merge() - see below.
I used dep to build the vendor tree but decided against submitting them in the PR and they are in the .gitignore as you can see.
Hopefully this is helpful to you, if not I'll just keep my fork and potentially add controller access as I'll need them.

Cheers, and thanks for sharing this in the first place.

-Stefan Engstrom (ENA)

[spellgen]

Another need for my use is the ability to specify an http client (that can be shared and re-used) - in my case I discover the ipam host as a raw host (specified by ip address) so I need to pass a Transport that skips cert verification.

I have implemented this by adding an http.Client to the Session object. It has a lock to protect against the use case where more than one go-routines are making calls off the same session.