Fix Linode provider

[koesie10]

In response to #323.

I've tested it with the Linode provider, and due to commit 19ca760, the order of the integration tests have changed. So, the failing test's number has changed from 25 to 27 in providers.json.

Moreover, the integration test for TXT records does not pass anymore because fixTxt has been removed (de44559#diff-cbc2e007a10f561a01f36d383d88aa80R259), which the provider relied on.

All other integration tests pass.

This fixes all those problems, but I haven't been able to test whether fixTxt breaks other providers.

[captncraig]

Feels to me like the linode provider itself should be populating the appropriate fields rather than relying on the core routine to fix it up after the fact.

[koesie10]

I would agree, but this was the previous behaviour, so multiple providers might rely on this behaviour being there. Therefore, I added it to the core routine.

[tlimoncelli]

True, but we decided it was unreasonable to ask every provider to get this right. We created .SetTargetTXT*() so they don't have to worry about the details. Also, if the struct changes, it puts the responsibility on us to fix the Set*/Get* functions. Letting providers do the wrong thing and fixing it later with fixTXT() was a bad decision on my part and I wanted to fix this.

Soon we'll be unexporting .Target and .Name to enforce all of this.

How about something like this? (I haven't tested it)
https://github.com/StackExchange/dnscontrol/tree/tlim_linode

Tom

[koesie10]

Alright, thanks for the draft, I did test it and the two lines commented out were needed due to the way the Linode API works. I've also changed other obvious references to .Target and .Name to use the getters/setters.

[tlimoncelli]

Thanks for the submission!