Copyedit `README.md` & `game.conf` (#2919)

README.md

 # Minetest Game
 
-The default game bundled in the Minetest engine.  
+The default game bundled in the Minetest engine.
 
-For further information, check 
-[this forum topic](https://forum.minetest.net/viewtopic.php?f=15&t=9724).   
-Also see the [Minetest Wiki](https://wiki.minetest.net/Subgames/Minetest_Game) 
-for more information.
+For further information, check [this forum topic](https://forum.minetest.net/viewtopic.php?f=15&t=9724).
+
+Also see the [Minetest Wiki](https://wiki.minetest.net/Subgames/Minetest_Game) for more information.
 
 ## Installation
 
-- Unzip the archive, rename the folder to minetest_game and
-place it in .. minetest/games/
+- Unzip the archive, rename the folder to `minetest_game` and
+place it in .. `minetest/games/`
 
-- GNU/Linux: If you use a system-wide installation place
-    it in ~/.minetest/games/.
+- GNU/Linux: If you use a system-wide installation place it in `~/.minetest/games/`.
 
 The Minetest engine can be found at [GitHub](https://github.com/minetest/minetest).
 
-For further information or help, see:  
-https://wiki.minetest.net/Installing_Mods
+For further information or help, see: [Installing Mods](https://wiki.minetest.net/Installing_Mods).
 
 ## Compatibility
 
-The Minetest Game GitHub master HEAD is generally compatible with the GitHub
-master HEAD of the Minetest engine.  
+The Minetest Game GitHub `master` `HEAD` is generally compatible with the GitHub
+`master` `HEAD` of the Minetest engine.
+
 Additionally, when the Minetest engine is tagged to be a certain version (e.g.
-0.4.10), Minetest Game is tagged with the version too.
+`0.4.10`), Minetest Game is tagged with the version, too.
 
 When stable releases are made, Minetest Game and the Minetest engine is packaged 
 and made available at [www.minetest.net](https://www.minetest.net/downloads/).

game.conf

-name = Minetest Game
-author = Minetest
-description = A basic exploration, mining, crafting and building sandbox game with no NPCs, monsters or animals. Minetest Game is usually used with mods added and many mods are available for this game. Reliably maintained by Minetest Engine core developers.
+name        = Minetest Game
+author      = Minetest
+description = A basic exploration, mining, crafting, and building, sandbox game with no NPCs, monsters, or animals. Minetest Game is usually used with mods added, and many mods are available for this game. Reliably maintained by Minetest Engine core developers.