Splunk SDK should not overwrite the environment except perhaps in its own SPLUNK_* namespace

[ctranstrum]

Any possibility to re-open #59 ?

It's a little silly that a driver library should dictate the environment to the entire app.

The solution proposed in the abandoned issue would be acceptable, in my opinion.

[ctranstrum]

I guess I should add, in case it wasn't clear, that this isn't just an academic concern. The splunk sdk overwrote the LOG_LEVEL environment variable in our application, and caused us a lot of lost time trying to track down and troubleshoot the issue. Of course now we have added a workaround in our code, where we specifically have to use a different environment variable name only in cases where we are using the splunk sdk, but this should have never been a requirement, and it both would simplify our code as well as minimize future confusion for others if this issue could be addressed in the splunk sdk.