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

entries/a7xpg.md

@@ -3,13 +3,11 @@
 - Home: http://a7xpg.sourceforge.net/, http://www.asahi-net.or.jp/~cs8k-cyu/windows/a7xpg_e.html
 - State: beta, inactive since 2005
 - Download: https://sourceforge.net/projects/a7xpg/files/a7xpg/
-- Keyword: arcade
+- Keyword: arcade, space, flight
 - Code repository: @see-home
 - Code language: D
 - Code license: 2-clause BSD
 - Code dependency: libvorbis, SDL
 - Developer: Kenta Cho
 
-Arcade space flier.
-
 ## Building