[FEATURE] Developer Tools

[phi-dbq]

This PR proposes tools and scripts to help getting started with developing Spark Deep Learning Pipelines.

• SBT plugin to locate Spark package dependencies
• Shell script to build Spark REPL launchers for Python2, Python3 and Scala.
• Docker files for building container images with the right dependencies.

[codecov-io]

Codecov Report

Merging #59 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master      #59   +/-   ##
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  Coverage   83.06%   83.06%           
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  Files          23       23           
  Lines        1234     1234           
  Branches        5        5           
=======================================
  Hits         1025     1025           
  Misses        209      209

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[jkbradley]

Discussed offline: This PR will be renamed and put aside, limited to the docker stuff only, and considered in the future. A new PR will have the README updates required for the 0.2.0 release.