descriptions of entries checked and either incorporated to keywords and inspirations or redundancies removed

entries/bitfighter.md

@@ -4,15 +4,13 @@
 - State: mature
 - Download: http://bitfighter.org/downloads/
 - Platform: Windows, Linux, macOS
-- Keyword: action, open content
+- Keyword: action, open content, space
 - Code repository: https://github.com/bitfighter/bitfighter.git
 - Code language: C, C++
 - Code license: GPL-2.0
 - Code dependency: SDL2
 - Assets license: GPL
 
-Outer-space combat action game.
-
 ## Building
 
 - Build system: CMake