[Downloader] Add controls and style for news and quests

Also clean up spacing and positioning.
[Downloader] Updated style of data directory selection
Merge remote-tracking branch 'GitHub-Vilarion/feature/gradle' into feature/gradle

Conflicts:
	illadownload/src/main/java/illarion/download/gui/GuiApplication.java
[Downloader] User directory and view selection

- The page to select the user directory is implemented now
- The selection of the pages to display is working now