v1.15.7

This is a release introducing some changes. First there is a new privacy setting you can
enable: additionally to Do-Not-Track Liferea now supports the Do-Not-Sell user data setting.

There is a major change to the enclosure (media attachments) handling. The built in media player
working on a "attachment" style list view under the item content was removed. Now enclosures
are added via HTML <audio> and <video> tags below the item content. The idea is to play those
purely with WebkitGTK support. Downloading is still supported by right clicking on those tags.

Finally a long standing issue was improved: when a feed does not provide item titles Liferea now
uses a teaser of the item content as the title. This for example fixes the usability of Mastodon feeds.

What's Changed

    * Add Sec-GPC header support via new preference to prevent user data selling.
      (Lars Windolf)

    * Drop enclosure list view in favour of embedded HTML5 <audio> and <video> elements
      (Lars Windolf)

    * Fixes #1332: Improve "*** No title! ***" for items without title
      (Lars Windolf)

    * Update appdata for 1.15.6 by @bbhtt in https://github.com/lwindolf/liferea/pull/1346
    * Allow building with libsoup 3.0.7 by @ittner in https://github.com/lwindolf/liferea/pull/1352
    * appdata: Update screenshot captions and remove dead link by @bbhtt in https://github.com/lwindolf/liferea/pull/1354

Full Changelog: v1.15.6...v1.15.7