Namespaced package

[yambottle]

Changes:

• Did all the changes in a separated branch namespaced_package
• Rename/Relocate packages
• Update related function calls
• Tested with Tutorial 01 and 02 without GPU

@dimitri-yatsenko Add you in the loop here as well.

[vijayiyer05]

This does seem to be on track to give the EXTRACT distribution a cleaner look & command-line interface.

A couple of comments:

• Some things which appear to be external dependencies (e.g. BrewerMap) appear under +internal
• One rule-of-thumb would be: a typical end-user should not need to use anything in +internal. Along those lines, if something "internal" appears in the Examples or Tutorials folders, I would suggest using a different subpackage. For instance, a +util package (for "utilities"). The downsampletime_pipeline function is one such instance.