Add `merge_method` and set new World Driven config

[TooAngel]

The .worlddriven.ini is extended with the merge_method option (merge, squash, rebase). https://developer.github.com/v3/pulls/#merge-a-pull-request

The config for this repository is changed to:

• 10 days per Pull Request
• 0 days additonal per Commit
• merge_method squash

Fixes #181

[worlddrivenbot]

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[worlddrivenbot]

Thank you for the review. This pull request will be automatically merged by worlddriven in 0 day(s) and 0:00:18.074117 hour(s). Current votes: 170/184.

Check the worlddriven status checks or the dashboard for actual stats.

[TooAngel]

This pull request was merged by worlddriven.