[Improvement] Remove scala dependencies from java client libraries

[doctorXWrites]

All haystack client libraries use haystack commons, which further depends upon scala libraries. The client libraries like haystack-client-java only require the haystack-idl(java). We need to reduce dependency from haystack-commons to just haystack-idl-java.

[doctorXWrites]

This has been fixed in release 0.2.6.
PR : ExpediaDotCom/haystack-client-java#100