Lumen 7.x dependency changes

Lumen 7 support

This may need some additional changes, but this quick change should get us over the initial hurdle.

Lumen 6.x support

1.0.6

Add illuminate 6.x compatibility to composer

Fix Guzzle option to suppress exceptions

1.0.5

Fix Guzzle exception suppressing option.

Log details of webhook call errors

1.0.4

Log webhook failure reasons.

1.0.3-dev

Support a delay to the WebhookCall dispatch.

1.0.3

Support a delay to the WebhookCall dispatch.