Removed entry point from all command line tools except `main`.

Fixes #49.
Add explicit setting to ensure main is never set for assembly.
Merge pull request #85 from ambiata/topic/single-entry-point

Removed entry point from all command line tools except `main`.
Added public travis build for visible sanity check on PRs.

Fixes #20.
Removing S3 test. This is not correct and doesn't actually work. The functionality will be addressed via Dictionary work.
Remove S3 from API/edge layers. It is not structured correctly to support multiple respository formats.

This will be further addressed by dictionary/meta-data changes. And
completed with full multiple storage backends in the future.