additions (from f-droid) and some link updates

entries/planet_conquest.md

@@ -0,0 +1,12 @@
+# Planet Conquest
+
+- Home: https://github.com/dftec-es/planetcon
+- State: mature, inactive since 2017
+- Download: https://f-droid.org/de/packages/com.dftec.planetcon/
+- Platform: Android
+- Keyword: strategy, turn based
+- Code repository: https://github.com/dftec-es/planetcon.git
+- Code language: Java
+- Code license: GPL-3.0
+
+## Building