Updated domains in README to checkmk.com

Change-Id: Ia4e622f246cdc0955f9a1d963c313a956a7b6d66

README.md

@@ -7,24 +7,24 @@ version is freely available for testing the Enterprise Edition in a
 non-production environment.
 
 Checkmk can be installed on Linux servers via DEB and RPM packages found on
-our [downloads page](https://mathias-kettner.com/download.php). The Enterprise
+our [downloads page](https://checkmk.com/download.php). The Enterprise
 Edition is also available as a virtual or physical appliance. The following
 short installation guides show how you can easily set up Checkmk and begin
 monitoring.
 
-Please visit our [website](https://mathias-kettner.com/check_mk.html) for more
+Please visit our [website](https://checkmk.com/) for more
 details.
 
 ## Getting started
 
 Please have a look at the [official
-handbook](https://mathias-kettner.com/cms_introduction.html) on how to get
+handbook](https://checkmk.com/cms_introduction.html) on how to get
 started with Checkmk.
 
 ## Building on your own packages
 
 It is highly recommended to use the prebuilt Checkmk packages we
-[provide](https://mathias-kettner.com/download.php). But if you really want to
+[provide](https://checkmk.com/download.php). But if you really want to
 build your own packages, you either need to download the source packages from
 our website or check out the [Git
 repository](https://github.com/tribe29/checkmk).