Issue installing alongside new Rector release (`v0.19.0`)

[u01jmg3]

From Composer

Problem 1
    - driftingly/rector-laravel 0.29.0 requires rector/rector ^0.18.5 -> found rector/rector[0.18.5, ..., 0.18.13] but it conflicts with your root composer.json require (^0.19.0).

I was led to believe that ^0.18.5 would allow ^0.19.0 but perhaps not when <1.0.0.

[driftingly]

Closed by #169