Feature Request: Add option for relative import

[SirusCodes]

It would be great if this package can change our absolute imports to relative imports.

Example 1
import 'package:my_app/lib/src/foo.dart'
to
import 'foo.dart'

Example 2

import 'package:my_app/lib/src/p1/foo.dart'
import 'package:my_app/lib/src/p2/foo.dart'

to

import 'p1/foo.dart'
import 'p2/foo.dart'

if imported in src
to

import '../p1/foo.dart'
import 'foo.dart'

if imported in p2

I would like to contribute to this feature but can anyone guide me with this?

[gleich]

See #63