Update main dependency to 3.0.0.
Update main dependency to 3.0.0.

The main lib used to check for the fattr 1.x library specifically, which
broke when fattr surpassed 2.0. The bug was fixed in main as of 3.0.0.

See: http://github.com/ahoward/main/commit/6709b8c429571f8348233a17378a134049323f78#diff-2

cristibalan/braid