Remove travis.yml

Signed-off-by: Ian Campbell <ijc@docker.com>

.travis.yml

@@ -1,21 +0,0 @@
-language: go
-
-go:
-  - 1.9.x
-
-env:
-  - TRAVIS_GOOS=linux
-  - TRAVIS_GOOS=darwin
-  - TRAVIS_GOOS=windows
-
-script:
-# We want native versions of the tools.
-  - go get -u github.com/golang/lint/golint
-  - go get -u github.com/gordonklaus/ineffassign
-  - export GOOS=$TRAVIS_GOOS
-# FIXME: For non-linux GOOS, without running `go build -i`, vet fails with `vet: import failed: can't find import: fmt`...
-# Note that `go build -i` requires write permission to GOROOT. (So it is not called in Makefile)
-  - go build -i github.com/linuxkit/linuxkit/src/cmd/linuxkit
-  - make local-check
-  - make local-build
-  - if [ "$GOOS" = "linux" ]; then make local-test ; fi