* Flattened sourcegroupsettings class hierarchy by moving cross compilation options to own base class
* QtProjectWizzardContentFlags constructor required correct settings object to reduce the need for type casting
* QtProjectWizzardContentPath constructors required correct settings objects
* moved SourcePaths from SourceGroupSettingsJava to SourceGroupSettingsJavaEmpty because they are not required for Gradle and Maven projects
* removed classpath from maven and gradle source group settings
* reuse code of SourceGroup for "show source files" in wizard
Allows for defining specific target triple of architecture, vendor, OS and environment as set of dropdown lists
in CXX source group setup.
bug id = 370
mlangkabel