Super fun happy-go-lucky bootstrap!

Too much to break down into individual comments.
Added upload-to-s3 code + unit tests
More unit tests
Super fun happy-go-lucky bootstrap!

Summary: Too much to break down into individual comments. Added upload-to-s3 code + unit tests. More unit tests. Added .arcconfig.

Test Plan: n/a

Reviewers: abahouth

CC: egor, esayle, abahouth, mhalverson

Differential Revision: http://107.23.59.21/D5
Fixing issues raised in http://107.23.59.21/D5
Moved the S3Object classes into their own file.

Also made the unit test function `present?` be a macro, not a fn, so that
we can tell which unit test fails :P
Added upload-sync-files! and upload-sync-directory!

Created unit tests for them, too.
A few changes to method-names in download town.
Added doc strings to everything in core.clj.
Made core.clj internally consistent in its usage of file/dir vs path.
Deleted download-sync-directory! since it was redundant to download-sync-files!
Merge pull request #1 from mhalverson/master

Added lots of upload code, polished up download code, added unit tests