Move config and watch into a base folder to prepare for multi-repo client

[mbohlool]

We need to separate our base and generated code so other users can create their own client and use our base utilities. This is a required restructuring explained here:

https://github.com/kubernetes-client/community/blob/master/design-docs/clients-library-structure.md

config and watch package has been moved into a base package as well as api_client rest and configuration classes. Symlinks created to make everything work as before.

[codecov-io]

Codecov Report

Merging #215 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #215   +/-   ##
=======================================
  Coverage   94.56%   94.56%           
=======================================
  Files           9        9           
  Lines         681      681           
=======================================
  Hits          644      644           
  Misses         37       37

Impacted Files	Coverage Δ
kubernetes/base/config/incluster_config.py	88.88% <ø> (ø)
kubernetes/base/config/__init__.py	100% <ø> (ø)
kubernetes/base/watch/__init__.py	100% <ø> (ø)
kubernetes/base/watch/watch.py	98.33% <ø> (ø)
kubernetes/base/config/kube_config.py	96.47% <ø> (ø)
kubernetes/base/config/config_exception.py	100% <ø> (ø)
kubernetes/base/watch/watch_test.py	96.42% <ø> (ø)
kubernetes/base/config/kube_config_test.py	92.22% <ø> (ø)
kubernetes/base/config/incluster_config_test.py	97.29% <ø> (ø)

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[mbohlool]

@dims this is ready to review.

[dims]

Looks like just things moving around :) /lgtm

[mbohlool]

Thanks