Version 4.2.3 brings several changes:

* fixed bug [Inbox still set as default first tab](https://github.com/XilinJia/Podcini/issues/10)
* cleaned up Inbox related resources
* removed info button in FeedItemList header
* added items count in FeedItemList header
* fixed bug in FeedItemList when filtered list has no items
* buildConfig is set in build.gradle instead of gradle.properties