readme: remove old content and add link to GSI wiki

README.md

 White Rabbit Timing Receiver in PMC format
 =
 
-How to check out and synthesize the PMC gate ware
-==
+Instructions for testing and commissioning can be found here:
+https://www-acc.gsi.de/wiki/Timing/TimingSystemPMCTestingAndCommissioning
 
-On Linux:
-
-<pre>
-mkdir pmc
-cd pmc/
-git clone https://github.com/stefanrauch/bel_projects.git --recursive
-cd bel_projects/
-git checkout pmc
-git submodule init
-git submodule update
-git submodule update --recursive
-
-Optional: make pmc
-Optional: Open project file bel_projects/syn/gsi_pmc/control/pci_pmc.qpf
-with Quartus
-</pre>
-
-Be aware that you need a Quartus 64-bit version to synthesize the design.