Added Option to Details Block

Pushed out v1.3.6 of Options for Block Themes plugin which adds an option to the Details block to close other Details blocks when opened thereby allowing a collection of Details blocks to take on some of the features of an Accordion Block.

This is a temporary solution as we believe an Accordion block is in production (as is a Tabs block) seeing as the Details block is not considered suitable to be used as an Accordion block in this way.