New Packaging Approach

[oconnormi]

Lots of changes here to make these scripts more portable.

Major Changes:

1. No longer released as a docker image, instead it will be a versioned zip file. (see notes)
2. Multiple environment files can be loaded from the entrypoint/environment directory
3. Added required binaries to internal bin directory
4. Internal bin directory is automatically added to the path by entrypoint.sh
5. all subscripts are now in entrypoint/library and entrypoint/entrypoint.sh will ensure the proper paths are wired up.

Deprecations

1. No longer necessary to set ENTRYPOINT_HOME, this is autocomputed at runtime now

Notes

The reason for not packaging as a docker image is to move the onus of managing ddf distribution dependencies to the individual projects instead of relying on a shared container image base.
Instead the only shared bits will be the entrypoint scripts and related binaries which can be pulled in via a single versioned zip file (on the github repos releases page)