Replace propel migrations with phinx

Summary: Replace propel migrations with phinx

Test Plan: N/A

Reviewers: allauthors, latent-codex-awalker

Maniphest Tasks: T2

Differential Revision: http://phabricator.latentcodex.com/D3
adding version of phinx yml to the repo
Merge branch 'T2_new_migration_process' of https://github.com/latentcodex/estimator into T2_new_migration_process