move DataClient from lookout to new sdk package

[smacker]

Lookout contains convenient wrapper for grpc data client.
It's meant to be used by analyzers, so only dummy analyzer uses it
currently.

This commit moves the wrapper into lookout-sdk to allow all analyzers
use it.

I put it into new sdk package which is higher level sdk for Go than
current pb. We also may reconsider which custom code belongs to pb and
move the rest into this package to separate low level auto generated
code from actual sdk API.

[se7entyse7en]

We also may reconsider which custom code belongs to pb and
move the rest into this package to separate low level auto generated
code from actual sdk API.

I think that's a good idea! 👍

[dpordomingo]

nice! thanks!

[carlosms]

LGTM about moving the code.

Before we merge this, I have a question about the destination folder.
In master we have:

• ./python for all the python SDK code
• ./pb for all the go SDK code

Now it will be:

• ./python for all the python SDK code
• ./pb and ./sdk for the go SDK code

Should we have instead ./go/pb and ./go/sdk?
I don't like breaking compatibility of the current imports, but I'm wondering if having the root folder of the go sdk ./ can bring more problems in the future, or be more inconvenient to use....

[se7entyse7en]

I also prefer having ./python and ./go instead of having go sdk in ./. Currently, it seems that SDK for Python is some sort of second-class thing, but I don't think that this is the case (correct me if I'm wrong). So in the end we'll have:

• proto - common definitions,
• python - for python SDK,
• go - for go SDK.

[smacker]

I think pb directory should be inside go.
I didn't move it because it's breaking change.
How about if I move sdk into go here and for pb we do another PR combined it with moving some code from pb to sdk?

[carlosms]

sounds good to me