renamed games folder to entries folder (also contained frameworks, libraries, ...) and added to the backlog

entries/flightgear.md

@@ -0,0 +1,19 @@
+# FlightGear
+
+_Flight simulator developed since 1997._
+
+- Home: https://www.flightgear.org/, https://sourceforge.net/projects/flightgear/
+- Media: https://en.wikipedia.org/wiki/FlightGear
+- State: mature
+- Download: https://www.flightgear.org/download/
+- Platform: Windows, macOS
+- Keywords: simulation, clone, inspired by Microsoft FLight Simulator
+- Code repository: https://git.code.sf.net/p/flightgear/flightgear
+- Code language: C++
+- Code license: GPL-2.0
+
+
+## Building
+
+- Build system: CMake
+