Revert "Mark index pagination Cuke wip (fails on Travis)"

Failures most likely due to Xvfb settings (see 1267a944)

This reverts commit 5f4a2281bf78c3f372cb21e32bdf70d612f95f1d.
API v2: Change boolean value to use true/false

While this is not the OpenProject API, we use true/false for other APIs and for other parameters in the application, like `layout=false`. true/false also seems more intuitive.
API v2: Document some useless code
Merge pull request #1905 from opf/fix/reenable-index-pagination-cuke

Revert "Mark index pagination Cuke wip (fails on Travis)"
Merge pull request #1911 from opf/hotfix/api_v2_rewire_parents_value

API v2: Use true/false as rewire parents value
Merge branch 'release/3.0' into dev