This changes introduce goreleaser, which does cross-compile and
package, as well as add version into go code. This change also
changes .travis.yml to allow to other users' forked repo.
This fixes#243 with following changes:
+ Optimize to fetch Pod from k8s client
+ Change to use cache always in DEL.
+ If failed to fetch the pod info from k8s clinet in deletion,
use cached delegates as emergency bailout
+ Add test cases for cache
fixed conflicts in multus/multus.go & multus/multus_test.go
Change the Network Attachment Selection Annotation long-form
interface name request JSON key from 'interfaceRequest' to
'interface' to conform with the V1 NPWG spec.
