Merge pull request #487 from John-Lin/readme-add-plugin-linen

README plugins list: add Linen CNI plugin

README.md

@@ -53,6 +53,7 @@ To avoid duplication, we think it is prudent to define a common interface betwee
 - [CNI-Genie - generic CNI network plugin](https://github.com/Huawei-PaaS/CNI-Genie)
 - [Nuage CNI - Nuage Networks SDN plugin for network policy kubernetes support ](https://github.com/nuagenetworks/nuage-cni)
 - [Silk - a CNI plugin designed for Cloud Foundry](https://github.com/cloudfoundry-incubator/silk)
+- [Linen - a CNI plugin designed for overlay networks with Open vSwitch and fit in SDN/OpenFlow network environment](https://github.com/John-Lin/linen-cni)
 
 The CNI team also maintains some [core plugins in a separate repository](https://github.com/containernetworking/plugins).