Remove common from CMakeLists.txt, README.txt, lua-api.txt and buildwin.sh

README.txt

@@ -9,10 +9,9 @@ and contributors (see source file comments and the version control log)
 In case you downloaded the source code:
 ---------------------------------------
 If you downloaded the Minetest Engine source code in which this file is
-contained, you probably want to download these projects too:
-  https://github.com/minetest/common/
+contained, you probably want to download the minetest_game project too:
   https://github.com/minetest/minetest_game/
-See the README.txt in them.
+See the README.txt in it.
 
 Further documentation
 ----------------------
@@ -92,13 +91,6 @@ $ wget https://github.com/minetest/minetest/tarball/master -O master.tar.gz
 $ tar xf master.tar.gz
 $ cd minetest-minetest-286edd4 (or similar)
 
-Download common (needed for minetest_game and some others)
-$ cd games/
-$ wget https://github.com/minetest/common/tarball/master -O common.tar.gz
-$ tar xf common.tar.gz
-$ mv minetest-common-* common
-$ cd ..
-
 Download minetest_game (otherwise only the "Minimal development test" game is available)
 $ cd games/
 $ wget https://github.com/minetest/minetest_game/tarball/master -O minetest_game.tar.gz
@@ -124,7 +116,7 @@ $ ./minetest
 Compiling on Windows:
 ---------------------
 - This section is outdated. In addition to what is described here:
-  - In addition to minetest, you need to download common and minetest_game.
+  - In addition to minetest, you need to download minetest_game.
   - If you wish to have sound support, you need libogg, libvorbis and libopenal
 
 - You need: