Correct typos in the install instructions

docs/installing.md

@@ -1,9 +1,9 @@
 # Installing
 
-First, you will need access to the game MPQ files.
-- First, locate `DIABDAT.MPQ` on your CD or in the GoG installation (or [extract it from the GoG installer](https://github.com/diasurgical/devilutionX/wiki/Extracting-the-.MPQs-from-the-GoG-installer)).
+First, you will need access to the game's MPQ files.
+- Locate `DIABDAT.MPQ` on your CD, or in the GoG installation (or [extract it from the GoG installer](https://github.com/diasurgical/devilutionX/wiki/Extracting-the-.MPQs-from-the-GoG-installer)).
 - For the Diablo: Hellfire expansion you will also need `hellfire.mpq`, `hfmonk.mpq`, `hfmusic.mpq`, `hfvoice.mpq`.
-- DevilutionX comes with [devilutionx.mpq](https://github.com/diasurgical/devilutionx-assets/releases/download/v1/devilutionx.mpq) which is also needed.
+- DevilutionX comes with [devilutionx.mpq](https://github.com/diasurgical/devilutionx-assets/releases/download/v1/devilutionx.mpq) which is required to run the game properly.
 - Chinese, Korean, and Japanese users will also need [fonts.mpq](https://github.com/diasurgical/devilutionx-assets/releases/download/v1/fonts.mpq) or the text will be missing.
 - For Polish voice support you need [pl.mpq](https://github.com/diasurgical/devilutionx-assets/releases/download/v1/pl.mpq)