Adds customer model
Adds Customers#index and Customers#show
Adds customer creation
Adds customer editing
Adds customer deletion
Adds version number
Merge branch 'release/v0.1.0'

* release/v0.1.0:
  Adds version number
  Adds customer deletion
  Adds customer editing
  Adds customer creation
  Adds Customers#index and Customers#show
  Adds customer model