Change versionstring to 2.2.0

src/doomdef.h

@@ -140,8 +140,8 @@ extern FILE *logstream;
 #else
 #define VERSION    202 // Game version
 #define SUBVERSION 0  // more precise version number
-#define VERSIONSTRING "v2.2"
-#define VERSIONSTRINGW L"v2.2"
+#define VERSIONSTRING "v2.2.0"
+#define VERSIONSTRINGW L"v2.2.0"
 // Hey! If you change this, add 1 to the MODVERSION below!
 // Otherwise we can't force updates!
 #endif