Fix hardcoded tenant name for job binaries

After the fix the current user's tenant is taken instead of one
from the Sahara config.

I think we can fix it better and I outlined my thoughts in the bug
comments. Current fix could be viewed as temporal until we agree on
something else. BTW it could be ported to stable/icehouse since it
does not changes Sahara API, unlike the fix I've proposed in the
comments.

Change-Id: Ifef76905cab313e451eb9e68f915738f33e11a25
Partial-Bug: #1306713
Made processes names case sensitive

Current approach "store name in any case, but search in lowercase" was
done to work with HDP uppercase processes. Since process manipulation
logic was moved to plugins, replaced approach to case sensitive use.

Closes-Bug: #1282806
Change-Id: I4a8d65b750135a8521f26c6e6c2d9311f3281b14
Removed migration-time config folders lookup

Search in 'sahara' folders in addition was needed before
renaming savanna to sahara. After renaming it is a default option.

Change-Id: I41fdf2198c0e5f013794cac5354fd5460798806b
Removed unneeded check on job type during job execution

Job type is checked during job creation. No need to check it during
execution. Plugin should check that cluster supports given job type,
but removed check had nothing to do with that.

Change-Id: I33a7806cfbc63d3dc26729efe83a23191a3dd527
Merge "Fix hardcoded tenant name for job binaries"
Merge "Removed unneeded check on job type during job execution"
Merge "Removed migration-time config folders lookup"
Merge "Made processes names case sensitive"
Fix and rework the configuration options

Change-Id: I3a13ef84d4aca80b2fd228ef1ee58e8eb7ae3324
Merge branch 'master' into spark-plugin