Adding new spec helpers file

[jwoertink]

Fixes #21

The file right now just requires the migrations. This is a required step in order to run specs with an app that's using Breeze.

Without this step, you'll get the following error:

❯ crystal spec


Finished in 281.44 milliseconds
0 examples, 0 failures, 0 errors, 0 pending
Unhandled exception: Breeze::BreezePipe wants to use the 'breeze_pipes' table but it is missing.

If you need to create the 'breeze_pipes' table...

  ▸ Generate a migration:

      lucky gen.migration CreateBreeze::BreezePipes

Which could be confusing for someone new to Lucky. You currently have to add require "breeze/db/migrations/**" which is fine, but we may want to add other additional helper stuff later. Now we have a file we can add additional things to.