make the sapcontrol SOAP XML webservice client importable

[stefanotorresi]

for external consumption, like in the Trento project.

[MalloZup]

I wonder if following standard golang pkg is better.

But I I think also lib , is less uncommon but still okaish. anyways nothing I can block as not maintainer. As personal pov , I would use pkg since project is using already a bit of the layout mentioned

[arbulu89]

Really appreciated @stefanotorresi

[stefanotorresi]

@MalloZup I thought about that but pkg would be ambiguous with the existing packaging directory, so I think lib makes it more clear that code in there can be used as an external library.