Update Debian packaging files, move manpage to section 6

Modified application of pull request #43 by bartbes
 - Kept binary in /usr/bin
 - Remove postinst/postrm scripts

platform/unix/debian/love.install

@@ -1,6 +1,5 @@
-usr/bin/love
-usr/share/man/man1/love.1
-usr/share/pixmaps/love.svg
-usr/share/mime/packages/love.xml
-usr/share/icons/hicolor/scalable/mimetypes/application-x-love-game.svg
-usr/share/applications/love.desktop
+usr/bin
+usr/share/applications
+usr/share/mime
+usr/share/pixmaps
+usr/share/icons