Preparing for 3.0.0 release

Fixing minor typos.

Preparing for 2.7.0 release.

Fixed `APIService` `overwriteRequest(handle:path:parameters:security:…

…)` to configure request with method POST instead of GET.

Preparing for 2.6.3 release.

Preparing for 2.6.2 release.

Preparing for 2.6.1 release.

Check that file exists before trying to remove it (#2).

Preparing for 2.5.2 release.

Allow uploadables to be added regardless of state.

Fixing typo.