Update the package's metadata

[fitodic]

Changed

• Moved the package's metadata to setup.cfg

Removed

• MANIFEST.in
• Centerline from the centerline namespace. To import the Centerline
  class, use from centerline.main import Centerline

[coveralls]

Coverage remained the same at 100.0% when pulling 68e92af on feature/package-metadata into 57a401d on master.

[coveralls]

Coverage decreased (-5.0%) to 95.035% when pulling d0da484 on feature/package-metadata into 57a401d on master.

[coveralls]

Coverage remained the same at 100.0% when pulling 68e92af on feature/package-metadata into 57a401d on master.

[coveralls]

Coverage remained the same at 100.0% when pulling 68e92af on feature/package-metadata into 57a401d on master.