Update the tests so they pass again following the release of phinx 0.4.6

[HavokInspiration]

This should not be merged right now

This phinx release and this PR shed some light on some migrations tests that were not done. Now that they are all running, I spotted a bug in phinx implementation of the mechanism to drop foreign key constraints with SQLite. I submitted a PR on phinx repo : cakephp/phinx#641

The test suite will be failing for SQLite until the change I will propose will be merged and a new phinx release is

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This phinx release introduced changes in the naming scheme the migration files / the migration classes should follow, breaking the tests.

This commit also removes the update() call after the dropForeignKey() calls : it was not necessary.

[HavokInspiration]

I pushed a new commit that contains a few things.

First of all, since nothing has moved on phinx's side, I decided to implement a temporary fix to fix the cause of the tests failures with SQLite. I'll remove it once (and if) the PR on phinx repo is merged.

While doing that, I noticed a defect : the Migrations class was not using the CakeAdapter but the Adapter from phinx which prevented the bugfix to fix anything. So I fixed this along the way.

Tests should be passing again now.

[HavokInspiration]

PR on phinx has been merged. We just need a release now for the tests to pass. I updated the code to remove the temp fix I added.

[HavokInspiration]

I pushed a commit where I change the dependency for phinx to dev-master. This way we have the merged changes from phinx and we can move on with this PR, #125 (after a rebase and a travis check), #62 (I might add some tests for this), target the min requirement for cake to 3.1 and start working on #128.

What do you think ?
This can be reverted when a new release of phinx is done.

[lorenzo]

I think that plan makes sense @HavokInspiration