Update composer.json snippet to reference v1.2.*

I just copied the version to my `composer.json` that you had in your `README.md`, but apparently it has some issues with Laravel 4.2, but it appears to be fixed in `1.2.*`. This fix is just to help people like me who are copy-paste happy and don't check the tags right off. =)

README.md

@@ -45,7 +45,7 @@ Add `kmd/logviewer` as a requirement to `composer.json`:
     ...
     "require": {
         ...
-        "kmd/logviewer": "1.1.*"
+        "kmd/logviewer": "1.2.*"
         ...
     },
 }